THE NORTHERN ENGINEER applied science in the north

Volume 17, Number 2 Summer 1985

. ,.,. STAFF: Editor, Carla Helfferich; Editorial Advisor, Lee Leonard; Associ· ate Editors, Barbara Matthews and K. Fiedler Morack; Editorial Assistant, Sue Keller; Finance Officer, Neta Stilkey. EDITORIAL BOARD: John Bates, DOTPF, Juneau; Joseph M. Colonell, Woodward-Clyde Consultants, Anchorage; Mark Fryer, Consulting Engi­ neers, Anchorage; Paul Goodwin, Special Assistant to the Commissioner of Education, Juneau; Keith B. Mather, Vice Chancellor for Research, UAF; Janet Mathesdi'i, Architect, Fairbanks; John M. Miller, Geophysical Insti­ tute, UAF ;·Tunis Wentink, Jr., Geophysical Institute, UAF; John Zarling, Mechanical Engineering, UAF.

The Northern Engineer, Vol. 17, No.2 THE NORTHERN ENGINEER The Geophysical Institute Volume 17, Number 2 University of Alaska-Fairbanks Summer 1985

CONTENTS______

A Learning Tour of Scandinavia: Energy-Efficient Living and Research by Richard Seifert and David Olivier ...... 4 Principal Achievements in Soviet Geocryology by Pavel I. Melnikov ...... 8

18 A Radiotracer Technique to Evaluate Gold Recovery by Gravity Concentrators by Daniel E. Walsh ...... 13

Monitoring Temperatures in an Offshore Arctic Well: A Brief Note by Alan Taylor and Alan Judge ...... 18

Diary of a Cheechako Builder by Ken L. Larson ...... 20

An Aufeis Case Study by W.J. Stringer, T. H. George, and R. M. Bell ...... 25

Back of the Book Noted, Meetings, Publications, Letters, Book Reviews, Errata .....30

COVER------­ Solar living in Denmark may look like this if the monitored design in the experi­ mental Hjortakaer village proves successful, as discussed in the article beginning on p. 4. The photo, taken by author Richard Seifert, was enhanced in the darkroom by Evelyn Trabant. 25

THE NORTHERN ENGINEER IISSN 0029-30831 is a quarterly publication of the Geophysical Institute, University of Alaska-Fairbanks- Dr. Juan G. Roederer, Director. It focusses on engineering practice and technological developments in cold regions, but in the broadest sense. We will consider articles stemming from the physical, biological, and behavioral sciences, as well as views and comments having a social or political thrust, so long as the view­ point relates to technical problems of northern habitation, commerce, development, or the environment. Contributions from other nations are welcome. We are pleased to include book reviews on appropriate subjects, and announcements of forthcoming meetings of interest to northern communities. "Letters to the Editor" will be published if of general interest; these should not exceed 300 words. (Opinions in the letters, reviews, and articles are those of the authors and not necessarily those of the University of Alaska, the Geophysical Institute, or The Northern Engineer staff and Board.) Subscription rates for The Northern Engineer are $12 for one year, $17 for two years, and $37 for five years. Some back issuesareavailablefor$3 each. Address all correspondence to THE EDITOR, THE NORTHERN ENGINEER, GEOPHYSICAL INSTITUTE, UNIVERSITY OF ALASKA-FAIRBANKS, FAIRBANKS, ALASKA 99775-0800, U.S.A. The University of Alaska is an EO/AA employer and educational institution.

The Northern Engineer, Vol.17, No.2 3 authors planned study tours to the first three of these countries to investigate the "action." In an example of great serendip· ity and luck we met in a lecture at the Norwegian National Building Research In· stitute in Trondheim, we struck up a cor­ A LEARNING TOUR OF SCANDINAVIA respondence, and the collaboration on this article resulted. Here's what we discovered Energy-Efficient Living and Research on these exciting learning tours, taken country by country.

DENMARK by Richard Seifert and David Olivier Less than a half hour's drive outside Copenhagen lies the Technical University of Denmark. This, the major technical uni­ versity of the country, was one of the first organizations to respond to the energy crisis of the early 1970s. The university's effort led to an architect-designed house now world renowned as the "Zero Energy House" (Nulenergihuset in Danish). It was planned to use no auxiliary fuel for energy, seasonally storing solar energy for use dur­ ing winter. This early attempt is not per­ forming as originally designed; it turns out that the 20,000 ·gallon storage tank has a poor thermal performance and loses heat too quickly for full storage to last the win· ter. Nevertheless, this experimental house established the Danes' commitment to the realistic and relentless pursuit of quality housing to lessen their considerable depend­ ence on petroleum fuels. In 1978, six model energy-efficient homes were built at Hjortakaer, a village near the Technical University. These were monitored for the first years of their existence, a project which has been com­ pleted. The houses incorporated diverse architectural designs, high insulation levels, airtightness and many test systems and trial technologies from window shutters to solar designs. One of the Hjortakaer Figure 1. One of the houses (a solar design) in houses is shown in Figure 1. Plans are now the six-unit Hjortakaer experimental village in complete for a new-generation house in­ Denmark. These houses were monitored for corporating the most successful details of performance for two years and have been WHEN IT COMES TO ACTION and the first houses. The plans include a hybrid sold on the private housing market. frugality in matters of energy conservation wall design, using load-bearing dense con­ and design, it doesn't take an astute observ· crete internally with timber frame and er long to figure out where to go. Denmark, wood sheathing on the exterior, and having Norway, Sweden, and Finland are the lead· 12 inches of mineral wool insulation. This ing places to visit if learning about energy is for a country at the latitude of Ketchi­ efficiency in buildings, latest technologies, kan, Alaska, and about the same heating and economic resourcefulness is your in· index (6800 degree-days using the Fahren­ terest. Unbeknownst to each other, both heit scale).

Richard Seifert is an energy and building specialist for the Cooperative Extension Service of the University ofAlaska in Fairbanks. Recently awarded a Fulbright Research Scholarship, he is in Norway studying solar energy at the University of Trondheim. David Olivier is an energy consultant in Buckinghamshire, England. He was the chief author of Energy-Efficient Futures: Opening the Solar Option (1983, Earth Resources Research, 258 Penton ville Road, London, England, N 19JY), a report studying how the United Kingdom could use energy more efficiently and move toward renewable energy sources.

4 The Northern Engineer, Vol. 17, No.2 Work is also continuing on an experi­ Table 1. Building Code Specifications for Sweden, 1985 mental timber frame house which was Details built in the last four years to test heating Building Element U-Value A-Value systems. This timber frame structure was Roof 0.021 47 12.5" mineral wool found to be among the most airtight dwellings in the world (0.005 air changes Walls 0.029 33 9.5" mineral wool or ac per hour). The house also provides an ideal research building since it consists Floor 0.035 28 7.9" mineral wool of a shell that can be manipulated for materials research purposes and for Windows 0.36 2.8 Triple glass, quad common testing the results of various heating and storage options. Alaskans would do well Airtightness Maximum 3 ac/hr to build several structures of this type to at 50 pascals pressure, test in the various climatic areas of the 0.15 ac/hr at normal use state. Denmark has high building costs and Ventilation Mechanical ventilation there is a premium on land. In response to 0.5 ac/hr to these factors some groups have formed housing collectives for educational or contrast to the older-style grist mills that damage were traced to leaky vapor philosophical purposes, much like the dot the countryside. barriers, which allowed moist warm air to early utopian communities of the last move upward by the stack effect through century in the eastern U.S. In a sense, the SWEDEN the ceiling into the roof space. To mini­ ideal of energy efficiency is only one of In 1985 Sweden is scheduled to enact mize this risk, vapor barriers are required many upon which members of the Danish the most rigorous and stringent building to be 8-mil polyethylene, ultraviolet sta­ communities have chosen to focus. One codes in the world. In a fundamentally bilized, or equivalent. such community which we both visited socialized country with a mix of fossil What does meeting these code require­ was the Overdrevet housing collective fuel- and nuclear-generated electricity ments cost? We were able to get an aver­ located near Arhus. Overdrevet has a low· (the latter to be phased out by the year age cost for a Swedish house that meets temperature community (district) heating 2010). and no store of fossil fuels, the code: it is $500 per square meter or system in which heat to the circulating Sweden has approached energy con­ about $47 per square foot. That is com­ water is partially supplied by solar energy servation with supreme Scandinavian petitive anywhere in the U.S., and most collected on the individual homes. The frugality, discipline and resolve. Table 1 of the Canadian nonmanufactured hous­ homes themselves are very well insulated shows the specifications for a residence ing is at least that expensive. This is prime -above Danish standards. Wood-framed evidence that superinsulated construction walls have 12 inches of mineral wool, from the new code regulations of 1985. does not have to be more expensive than masonry walls have 8 inches, and roofs Sweden has had problems in moving so rapidly to superinsulated, airtight hous­ conventional structures. In addition, have 12 to 18 inches. The windows are ing. Lessons learned provide a valuable Swedish public response to the heavily triple glazed. experience to Alaskans. In fact Alaskans insulated and airtight construction has The community organization is based are seeing homes built now that include been encouraging. According to people on individually owned houses combined the same design erFors that were made in who were interviewed by both authors, with common ownership of land. A home Swedish homes built in the late 1970s. most in Sweden believe that problems at Overdrevet could be purchased for The problem homes were built slab-on­ with the increased insulation and air­ $65,000 U.S. at the time of our visit; grade; they were superinsulated and tightness have been solved and that the a would-be homeowner had to pass a vote relatively airtight. The vapor protection only remaining difficulty is with the vent­ of acceptance by the rest of the com­ for the slab was inadequate and allowed ilation. munity before the purchase was possible. moisture to evaporate into the living The Swedes are striving to overcome The collective also owns its own 55­ spaces, producing severe problems of that problem too. All new Swedish homes kilowatt wind generator which supplies condensation and mold growth. The have mechanical ventilation systems. Two the bulk of the electricity used in the vapor leakage was a major factor in main technologies are being used. Balanced community. The surplus power generated making the situation particularly severe, ventilation, with both supply and exhaust is sold to the utility grid. Utilities in Den­ and the air change rate in these houses ducts, can be used with an air-to-air heat mark pay about 60 percent of the price at was 0.1 per hour or less. This experience exchanger to reduce energy requirements. which they sell electricity to consumers is quite familiar to the first author, who It provides a more comfortable option for the wind-generated power. has seen a veritable epidemic of conden­ than the simple but less costly exhaust Wind-generated power is now in evi­ sation problems with recently construc­ ventilation. The latter system puts a dence across the Danish countryside in ted airtight housing in interior Alaska. negative pressure on the house and the form of numerous medium-sized Sweden addressed the problem by re­ utilizes vents under windows or at other windmills. A bit over 1 percent of Danish quiring mechanical ventilation in the convenient places for air intake. Use of a electricity now comes from the wind, 1985 building code (0.5 air changes per heat pump with the exhaust-type system mostly from machines in the range of 50 hour). to heat domestic hot water or for space to 60 kilowatts. These new windmills Inadequate roof vapor barriers also heating is a conservation measure that has provide a lovely and complementary caused trouble. Many cases of moisture been applied also.

The Northern Engineer, Vol.17, No.2 5 Figure 2. A view of the interior of a nine-unit condominium in the coastal city of Landskrona, Sweden. The "street"side of these houses (shown here) actually faces a private glass-covered atrium area which is the jointly shared property of all the condo owners. Sheltered from the weather, the space serves as a park, picnic, and children's play area; its moderated environment also has energy conservation advantages.

alent of two average city blocks. The units are in fact two long condominium units facing each other with a glass­ enclosed street between them. The interior is shown in Figure 3. These structures are imposing but have appeal from the point of view of modifying the environment of the street. On the day of our visit the temperature was about 24° F with a 20-knot wind blowing off the ocean. The immediate sense of shelter To understand domestic housing eco­ architect responsible for the design of and comfort one experiences upon nomics fully in Sweden, one must realize these units was Ann Thulin, an expatriate entering Gtlrdstlkra (the name of the that the financing mechanism for the American who also owned one of the neighborhood "dwelling") is memorable homes is almost entirely a simple state condominiums and was the president of and speaks well of the psychological value housing loan, an index-linked mortgage the condominium association. The unit of this approach to urban architecture. with first-year payments of less than 5 had partial solar heating and employed But how does it fare economically? percent of the sum borrowed. In this con­ heat pumps for space and water heating. It appears that the scheme's main benefit text the payback for energy conservation The energy efficiency of this system met is in the great savings in maintenance construction features can be 8 to 10 the 1985 building code of Sweden and costs to be had over those of a stan­ years, but the home buyers see only a has the advantage of modifying the dard street. Maintenance of all the small increase in the mortgage payment climate in a large entry common area as "streetfronts" of the homes is also and reap at the same time immediate well as modifying the temperature of the reduced greatly. There is evidence that savings in energy costs. The government walls facing the common. Of all the new the scheme will at least break even. is banking on the value of energy savings living concepts we saw in Sweden, this We cannot leave the Swedish section in the long term-a noble achievement for example was the most aesthetically and of our learning adventure without noting an elected system. physically pleasing. the home of Dr. Mats Wolgast of Upp­ In the Sktlne region of southwestern In the nearby community of Eslov sala. Uppsala is at about the same latitude Sweden, we visited the sites of two new the concept of glass enclosures used to (60°N) but has fewer heating degree-days experimental glass-enclosed multifamily modify a common public area is taken to (8000) than does Anchorage, Alaska dwellings. The first was a nine­ the large scale in a neighborhood-sized (10,950). Dr. Wolgast is a professor of condominium unit designed by the (400 meters long by 50 meters wide!) medicine at the University of Uppsala, Landskrona Group, and it was-appropri­ multifamily dwelling covering the equiv- and his contribution to the Swedish ately-in the coastal city of Landskrona. This project demonstrated a most elegant and appealing use of a greenhouse to provide a large enclosed sunlit courtyard which was a common area for all the tenants of the condominium. A photo of this courtyard is shown in Figure 2. The

Figure 3. The interior "street" of the Girdsikra project in Eslov, Sweden. Here the concept of using glass to moderate the environment of the street area is expanded from that shown in Fig. 2 ( Landskrona). Girdsikra is 400 meters long with a fully enclosed street between the Jines of clus­ tered housing and service units. The effect is positive from the environmental moderation standpoint: it is warm and a pleasant place to be in the colder months. But the aesthetic effect is less appealing than the Landskrona example- it has the feel of a large shopping center with some very "industrial-looking" features.

6 The Northern Engineer, Vol.17, No.2 energy scene was to be a radical insu­ The advantage of such a large number of lator. He built one of the first super­ test houses is that so many diverse insulated homes in Sweden, and first options can be tested for their perfor­ demonstrated their large energy savings mance and value and directly compared over the conventional designs. to other options. This ideal research The house we visited was in a sub­ arrangement would be useful for accom­ division in a very quiet suburban resi­ plishing the tests needed for housing in dential area outside the city of Uppsala Alaska as well. called Sunnersta. The Wolgast house is Several of the Heimdal homes have at­ externally indistinguishable from the tached sunspaces (Fig. 4) and a method other houses in the subdivision and in of storing solar gain for use at later times. most visible features is completely Most of the storage systems utilize unremarkable. But Mat's home is a stellar rock storage and active techniques performer in energy conservation. He employing air or water to move the heat heats an area of 1300 square feet with a to storage. During our visit in March combination of electric resistance heating 1984, the sun was shining and the sun­ of 1300 kwh per year and a wood stove spaces provided an impressive vantage in which he burns less than half a cord of point from which to consider and discuss wood (1 cubic meter per year). In Alaska the houses. The outdoor temperature on at Fairbanks prices this would cost about this day was 3°C (38°F) and the sunspace $193 per year. The Wolgast home has was 25°C (77°F). Heat was being de­ quadruple glazing in all windows, 18 livered to storage and a palm tree was inches of mineral wool insulation in the soaking up the solar gain. At a latitude roof, 10.6 inches in the walls, and 8 north of 63°, Trondheim's sunspaces per­ inches in the floor. The home is very air­ form similarly to those in interior Alaska, tight but has never been tested for the and in fact the Norwegians find it diffi­ Figure 4. Architect Johannes Gunnarshaug true infiltration rate. Dr. Wolgast seems cult to justify sunspaces using an energy explains the concepts and features of one of the to be a bit obsessive about air quality, cost vs. benefit argument. The best per­ fourteen experimental houses in the Heimdal and he consequently has an air-to-air heat formers from an energy conservation project, the largest experimental housing village in Norway. exchanger with an air filtration system. standpoint at Heimdal are those homes His home is so successful in this regard with improved airtightness and superin­ that a special receptacle was set aside to sulation. The houses all have airtightness CONCLUSIONS measure dust accumulation in 1978 and below 1.5 air changes per hour at 50 Scandinavia is indeed the leading area has since collected 0.1 mm of dust pascals pressure, which is three times in the high latitudes in energy efficiency (second author's estimate). better than the national code requirement and building design. In addition to this, it of 4 air changes per hour at 50 pascals appears that this success is largely attrib­ pressure for low-rise homes. NORWAY utable to the working collaboration In contrast to other countries of Glazings have been thoroughly re­ between the research institutes and the Scandinavia, Norway is rich in both searched as well at the Norwegian building and construction industry in all hydroelectricity and petroleum. Yet this Building Research Institute (NBI) in of the countries visited. The public has has not seemed to affect Norway's resolve Trondheim. NBI researchers concluded offered its support but has not led the to maintain a high energy-efficiency stan­ that few of today's coated, double­ movement. It is here that perhaps the les­ dard. The present standard is very close glazed argon-filled units perform better son lies for those wishing to achieve some to that of Sweden. This is especially im­ than standard clear triple glazing, and the degree of success in the critically im­ pressive since the cost of electricity, for double units usually cost more. The glass portant and opportunity-rich area of instance, is only 3.67 cents per kwh, in these double-glazed units is similar energy-efficient living and home design. a price equivalent to fuel oil at $1.08 per to that with the low-emissivity infrared The research and private sectors must gallon. reflective coating that can be purchased provide each other with mutual support Norway's largest and most diverse in the U.S. today. The disappointing and trust to undertake the search for op­ housing research project is the Heimdal performance of the units is due mostly to timum housing which is profitable to project near Trondheim. This project the decrease in solar gain caused by the build and affordable to buy and live in. consists of 14 two-story residential-style low-emissivity film. Government financial subsidy is pres­ houses, each of which is heated by means Norway is also applying the concept ent in some of the Scandinavian coun­ of an experimental technology or by a of large glass enclosures to modify the tries, and it is certainly a factor in the solar feature with superinsulation in environment, similar to those in use in building industry's stability. However, the various combinations. Some of the Landskrona and at G!lrds!lkra in south­ experience has been that energy-efficient homes also have heat pumps. In Figure 4, ern Sweden. In fact, the Landskrona housing does not cost significantly more the architect is shown explaining the Group of architects also designed the than less efficient standard housing. scheme of one of the homes in its sun­ Royal Garden Hotel in Trondheim, Scandinavia continues to provide quiet space. The homes typically use about probably the first hotel in the world leadership and effective examples of 19 million BTUs of heat for the season; to have an atrium constructed of coated efficient living through careful research most are about 1300 square feet in size. double glazing. and good material design. +

The Northern Engineer, Vol.17, No.2 7 Principal Achievements in SOVIET GEOCRYOLOGY by Pavel I. Melnikov

Permafrost Institute in Yakutsk, Siberia, 1974. (Photographs in this article are by J. G. Roederer.I

GEOCRYOLOGY is the science that departments concerned with the econom­ including rare, very valuable, unique, or deals with the composition, structure, for­ ic development of the northern regions much sought-after minerals. mation and development of frozen, freez­ are also contributing to the development Resource development in the region ing, and thawing rocks, as well as processes of this science. All of the geocryological was impeded by the existence of perenni­ and phenomena in the permafrost zone of research and studies on the territory of ally frozen rocks and soils. Before any in­ the earth's crust. the Soviet Union are coordinated by the dustrial program could be launched, it was In the Soviet Union, the body respon­ Scientific Council for the Cryology of the necessary to carry out fundamental studies sible for leading geocryological research is Earth of the USSR Academy of Sciences. and devise methods of constructing build­ the Institute of Permafrost of the Siberian Geocryology as a science emerged in ings, pipelines, roads, and aerodromes, of department of the USSR Academy of the Soviet Union in the 1920s. It was not mining minerals and of cultivating lands Sciences, which was set up almost a quarter until the 1930s that it began to grow vig­ suitable for farming. of a century ago. Moscow State University orously, for it was during that decade that The natural wealth of the eastern and and the institutes of the USSR Ministry the USSR started opening up its northern northern regions is now being tapped in of Geology, the USSR State Building territories, lands which even then were rec­ a planned and rapid fashion. As the years Committee, and the other ministries and ognized as being rich in natural resources, go by, these regions acquire increasing

Academician Pavel I. Melnikov is director of the Institute of Permafrost of the Siberian department of the USSR Academy of Sciences, chairman of the Scientific Council for the Cryology of the Earth of the USSR Academy of Sciences, and president of the International Permafrost Association. This article was preparedby Dr. Melnikovas a news release in September 1984. The photographs were taken by Juan G. Roederer, director of the Geophysical Institute, UAF, during various trips to the Soviet Union.

8 The Northern Engineer, Vol. 17, No.2 significance in supplying the USSR with fuel, energy, and minerals. There is an extensive program under way to develop the northern part of the Soviet Union as specified in its economic development plan for 1981 through 1985. Under this plan, for example, work will continue to establish the southern Yakutian territorial production complex, and to complete the 0 KAZAKHSTAN construction of an open-pit coal mine, an ore-dressing plant, and the first section of the Neryungri thermal power station. Work is going ahead to develop the zone around the Baikai-Amur Railway line, whose construction is nearing completion, Map of the USSR with many of the locations and great efforts are being made in other referred to in text. The inset shows the USSR (black) in relation to other parts of the world. regions of the USSR that are situated in the permafrost zone. Scientific results and recommendations A map (not given here) showing the fundamentally new results have been ob· of permafrost experts are being put to thermal flux inside the earth has been tained on the physics of heat exchange in use to implement programs for the eco­ compiled for the first time, covering the snow and vegetation covers. A new trend nomic development of the north. How­ entire zone of permafrost in these re­ has emerged in the earth sciences: the ever, since the scale of work is growing all gions. Areas with the lowest thermal flow thermal physics of landscapes, which is the time, scientists must devise more (the center of the Siberian platform) and based on an energy (heat) balance method effective methods of erecting buildings, the highest thermal flow (the Verkhoyansk that makes it possible to characterize laying roads and oil and gas pipelines, meganticlinorium) have been established quantitatively heat and moisture exchang­ and building storage facilities, as well as as well as thermal features of basin struc­ es between individual landscapes. providing better recommendations on the tures associated with the oil and gas Important studies have been pursued rational use of natural resources. deposits of the Siberian platform. The in the thermal physics of cryogenic phe­ Fundamental research dealing with the­ great extent of abnormally thick frozen nomena. A theory of the thermal erosion oretical and regional geocryology covers a layers that are not in equilibrium, and of of shorelines has been developed, allowing number of problems. These embrace the heat conditions that do not correspond a number of scientific and practical prob­ thermophysical principles of the forma­ to the contemporary climate but retain lems to be solved essential to the proper tion and development of the frozen- rock the relict features of the colder past development of natural resources in the (cryolite) zone, connections between the epochs, have been established. coastal zones of water bodies. The main earth's thermal field and geological struc­ A theory of geothermal fields is being principles of predicting thermal erosion tures, the thermal evolution of the cryo­ successfully developed. Analytical models have been formulated and, for the first lite zone under natural conditions and of geothermal fields for homogeneous and time, a universal procedure has been de­ under the influence of human activity, nonhomogeneous media in dissected to­ vised for predicting changes in shorelines and regularities governing thermal ex­ pography have been created. Methods have in the cryolite zone. These investigations changes in the atmosphere/ground cover/ been developed for interpreting geo­ make it possible to tackle scientific and soil system. thermal data and for making descriptions practical tasks of interest in the develop­ from a limited amount of data. ment of natural resources in the coastal RESULTS AND ACCOMPLISHMENTS For the first time in the USSR and the zones of arctic seas and in maintaining man-made reservoirs. The results obtained have helped to world, comprehensive investigations have As a result of geological and permafrost determine the way in which the surface been carried out into energy exchanges studies, the fundamentals of cryolithology temperature and the freezing of rocks are in the atmosphere/ground cover/soil sys­ have been established. This new scientific influenced by the climate and by water tem in various permafrost climatic zones. discipline deals with the distribution of exchanges with the atmosphere in various These investigations have made it possible underground ice in frozen rocks depending landscapes and natural zones. We now to characterize in quantitative terms the on their genesis, conditions of accumula­ know thermal conditions within the basic input-output components of heat and tion, and the degree of freezing of deposits. geostructures of the Asian north: the moisture exchanges between the atmos­ West Siberian shield, the Siberian plat­ phere and frozen rocks and to ascertain A method of solidification-facies analy­ form, and the Verkhoyansk-Chukotka the climatic conditions that govern sea­ sis has been adopted in the practice of geo­ region of folded-uplifted mountains. sonal and perennial freezing. A number of cryological works. Cryogenic textures have

9 The Northern Engineer, Vol. 17, No.2 Street in Yakutsk showing effects of melting ice and permafrost, 1974.

the charge on the surface of the ice and of the mineral skeleton. Regular studies are made of geocryo­ logical conditions in the alpine regions of Kazakhstan and central Asia. The area taken up by perennially frozen rocks in these regions is 170,000 square kilometers, or about six times that of ground glaciation in the central Asian mountains. The cryo­ lite zone in loose detrital formations is no more than 200 meters thick and may reach 360 meters in some harder rocks. Geo­ been classified according to geological­ been established that intensive physical cryological conditions essential to the genetic principles and a geological model and chemical processes occur not only in formation of glacial mud flows, which are proposed for their formation during the the active layer but also deeper, at the a constant threat to many cities in central surface and underwater solidification of level of seasonal temperature variations in Asia and Kazakhstan, have been studied. rocks. the negative values range. A direct link has been established in recent On the basis of a solidification-facies The phenomenon of the negative polar­ decades between the activation of glacial analysis and paleontologically dated sedi­ ization of rocks spatially associated with mud flows and the retreat of glaciers. The ments in the key sections of Yakutia, it cryogenic boundaries has been discovered glaciers left behind ice-filled morainic has been proven that the age of permafrost and studied. This phenomenon caused massifs which, when thawing, are potential in the basin of the Aldan River is well in scientists to review the theory of induced sources of glacial mud flows. The institute excess of 300,000 years and that peren­ low-frequency polarization of ion-con­ has recommended measures for stabilizing nially frozen layers within their present ducting rocks and also to assess screening unsteady moraines with talus by means of boundaries have never disappeared totally. effects in a horizontally layered medium artificially freezing their talus slopes into Evidently perennially frozen rocks have by using the induced polarization method a solid mass. existed throughout the Pleistocel')e and for probing. Methods have been elaborated for Holocene eras. A system has been devised to model mapping rock glaciers; data have been Comprehensive exploration of under­ induced low-frequency electrochemical obtained on their structure; and their ground waters in the frozen zone of the polarization of rocks to determine the rates of advance have been determined. earth's crust, including the analysis and possibility of using polarization in study­ The role of rock glaciers in transporting synthesis of extensive hydrogeological ing the structure, composition, and chang­ products of rock destruction has been findings gathered by various organizations, es in geological formations. The potential assessed and the need demonstrated for has made it possible to divide eastern of the induced polarization method in taking their movements into account when Siberia into permafrost-hydrogeological investigating upper layers of the cryolite planning construction projects high in the zones. This extensive territory, covering zone has been ascertained. mountains. some eight million square kilometers of The institute's geochemists have dis­ Investigations connected with envi­ the Soviet Union, has been mapped for covered that organic compounds are selec­ ronmental protection are being expanded. the first time on a scale of 1 :2,500,000. tively adsorbed onto the surface of oxides For the first time, a map of Yakutia (not The map (not given here) shows the and ice, and they have established that given here) has been compiled, showing permafrost-hydrogeological regions and substances having strictly defined ioni­ the degree of resistance of its territory to contains a great deal of information. zation potentials are, similarly, adsorbed anthropogenic effects. In recent years the Institute of Perm a­ from water solutions onto the surfaces of frost of the Siberian department of the oxides and ice. A connection has been PRACTICAL APPLICATIONS USSR Academy of Sciences has been found between the electron structure of working on geophysical methods to inves­ anions and their capacity for incorpora­ The institute takes part in investi­ tigate the dynamics of physical and chemi­ tion in the crystal lattice of ice when gations and feasibility studies for nearly cal processes. These can be used to study electrolyte solutions freeze. It also has all key construction projects in Siberia, changes during the year in the physical been found that the rate of migration of the Far East, and the Far North, as well and chemical condition of rocks in the salts in frozen sands, in the absence of a as in drawing up recommendations for the upper levels of the cryolite sphere. It has temperature gradient, is determined by rational use of natural resources and in

10 The Northern Engineer, Vol. 17, No.2 Apartment construction on permafrost terrain in Yakutsk, 1974. developing better methods for construc­ tion on frozen ground. Geocryological conditions have already been described in all of the diamond­ producing pipes, tin ore deposits in the northeastern USSR, coal deposits in southern Yakutia, and primary deposits of gold and nonferrous metals that are under development. Long-term geocryological studies in the Baikai-Amur Railway zone have been completed. Geocryological maps on a scale of 1 :50,000 and scientific descriptions of the region have been of ground produced by the laying of north­ on the true electrical conductivity of compiled. These works reflect modern ern gas pipelines. A provisional guide has frozen layers in diamond-bearing districts views about the basic characteristics of been compiled for protecting landscapes down to a depth of 150 meters. Technical frozen ground in the north of the Amur when gas pipelines are laid in the Far facilities have been developed for raising region, Khabarovsk Territory, and areas North. This is the first time a comprehen­ labor productivity in inspecting prospect­ near Lake Baikal and in southern Yakutia. sive approach to protecting the natural ing boreholes. It has been shown that frozen rocks are environment during a major construction The Institute of Permafrost, together preserved over large territories owing to project has been tried in the northern with the Yakutniproalmaz organization, the specific conditions of the surface cover USSR. has proposed a new and better type of and not to the climate. Therefore, when A great deal of applied research has foundation construction for districts with these territories are developed and the been done regarding agriculture. A series perennially frozen ground: reinforced insulating surface cover is dislocated, of works has been completed on methods concrete piles provided with built- in their degradation-with all the negative of basin and sprinkler irrigation on hay cooling systems with a naturally circulat­ consequences-is inevitable. The Institute and feed crop areas in central Yakutia. A ing agent. They are used with success in of Permafrost has forecast changes in the procedure for irrigation has been worked construction, reduce labor requirements geocryological conditions when the east­ out, and recommendations have been considerably, cut down on the amount of ern zone of the Baikai-Amur Railway is issued for raising soil fertility. building materials, facilitate work, and developed. Researchers have studied surface de­ add to the service reliability of structures. Fundamental research in engineering formations arising when underground ice One new concept to consider is bored geocryology has helped to solve key prob­ melts during the creation of arable lands. and filled piles. Our investigations have lems in controlling the temperature of In central Vakutia, between 20 and 30 shown that their bearing capacity in foundation ground, improving farm lands, percent of the newly established plow­ perennially frozen ground is 1.5 to 1.8 and restoring damaged landscapes. The lands go out of use in two to three years times higher than in the case of conven­ efficiency of plastic foam insulation in re­ because of trenches 1.5 to 2 meters deep, tional precast reinforced concrete piles. ducing the thawing depth of frozen ground produced as veins of ice melt away. Rec­ Successful experiments have been staged has been determined. The completion of ommendations have been given for select­ to enhance the effect of cooling devices these investigations made it possible to ing areas fit for plowing. and of the freezing of foundation ground start work on a very promising method of A lot of attention has been given to through thermal insulation of the surface. regulating the thawing depth and the the problem of using underground water It has been recommended that seasonal temperature of the ground. This method supplies. Original principles for assessing cooling devices be used when building offers the possibility of increasing the underground water resources and new low-cost and relatively easily erectable bearing capacity and dependability of designs for water intakes have been sug­ earth dams up to 20 meters high, with an structural foundations. gested. Effective methods have been intro­ ice- impermeable core, creating reservoirs Comprehensive studies conducted in duced for preventing water- intake holes for drinking water and for irrigation. The northern Siberia over many years have from freezing over. efficiency and dependability of such struc­ yielded recommendations for protecting A procedure for and methods of electric tures have been proven in the diamond landscapes from destruction and have logging of frozen rocks in dry boreholes mining industry. offered ways of choosing construction have been devised and actually applied. Many years of thermophysical inves­ sites and of revegetating scarred patches For the first time, data have been obtained tigations carried out by the institute on

The Northern Engineer, Vol.17, No.2 11 the dam of the Vilyuy hydroelectric power station have ( 1) established the main laws governing heat and mass transfer in the large fragmented rocks of the support prism and in the hard fissured rocks of the dam foundation and (2) determined the intensity of water filtration. Valuable data were obtained and later used in de· signing hydroelectric stations in other regions of perennially frozen rocks. In view of the rapid development of the northern areas, the use of perennially Construction site showing the foundations of the new Polar Geophysical Institute building in Murmansk, USSR, 1984. frozen ground as an environment for engineering structures is of considerable interest. This is dictated by the require· ments of rational environmental manage· ment and economic expediency. One way of reducing the adverse effects of eco­ nomic activity on the natural environment is the effective use of underground space. The Institute of Permafrost has developed a new technology for building under­ ground holding tanks in frozen ground. It is safer, simpler to execute, and much more productive than existing methods of drift-mining. Underground reservoirs in frozen sediments are designed to store oil products, water, and other substances. In Yakutia's farming areas, such vessels have been used advantageously for cooling milk and supplying the farms with water in the summer. Geocryological research is of great im­ Bratsk Dam in Siberia, 1971. The first section of the dam with the power plant comprises about one· portance in the development of arctic fourth of the total length of the structure. shelf deposits. The institute has con­ ducted experiments using sea water to create an artificial ice island on the Kara Sea shelf for drilling wells. Quantitative characteristics of heat transfer needed for the development of an optimum tech­ nology for carrying out production ex­ periments have been obtained for the first time in Soviet science. In the same area, studies are under way to develop methods for laying buried gas pipelines with the use of thermosiphon anchors. Information has been obtained on the formation of the temperature field around anchors and its dynamics in the annual cycle. Geocryology in the USSR, overcoming various difficulties of a scientific and organizational character, is developing successfully. Soviet researchers have sig­ nificant achievements to their credit in

12 fundamental and applied research, and Terewatt (10 wattl generators in the Bratsk hydroelectric power plant, 1971. When built, it was are recognized by foreign scientists as be­ the largest power plant of its kind in the world, and is now second only to that at ltaipil, Brazil. ing among the world leaders in this field. +

12 The Northern Engineer, Vol.17, No.2 A RADIOTRACER TECHNIQUE TO EVALUATE GOLD RECOVERY BY GRAVITY CONCENTRATORS by Daniel E. Walsh

OVERFLOW DISCHARGE t

THE IMPORTANCE of gravity concen­ tration processes is often overlooked, but t---4"VICTAULIC CPLG. as recently as 1973 in the United States, the value of ore treated by gravity meth­ FINDER CLEARANCE ( VFC l ods was more than double that treated by froth flotation. Gravity processes are especially important in the treatment of gold placer ores, which may have a grade 3 3 as low as a.aa5 oz/yd (2a3 mg/m ). and ----3"VICTAULIC CPLG. which may require concentration ratios '-----PHENOLITE ANTI-FRICTION DISC on the order of 1 : 1as to 1 : 1as. Though I-----SPRAY CHAMBER the capital and operating costs of gravity concentration depend on which process is used, it is always less expensive than other methods of concentration, such as ~ magnetic, flotation, or leaching, and is UNDERFLOW DISCHARGE often a prerequisite for bulk reduction Figure 1. Profile cross section of a 4-inch compound water cyclone (CWC). 2 before one of these other beneficiation processes is used.1 The surge in gold prices during the in this paper are stated in Tyler mesh prices, a detailed study of the fine gold late 197as and early 198as was followed scale.) recovery characteristics of gravity concen­ closely by a renewed interest in gravity In Alaska, the placer mining industry trators needs to be conducted. concentration processes, especially in was hesitant to adopt fine gold concen­ The Mineral Industry Research Labora­ concentrators claiming efficient recovery trators because of the lack of reliable, tory (MIRL) of the University of Alaska­ of fine placer gold. Cones, spirals, spin­ accurate, and reproducible data on con­ Fairbanks has already taken the first ning bowls, jigs, and cyclones are all con­ centrator efficiency. In most cases, con­ step in such a program. A four-year study sidered potential concentrators of fine centrator evaluation was based on a of a fine gold concentrator culminated in gold. (Fine gold, in this context, includes limited number of tests run on placer ma­ early 1985 with the development of a not only that gold finer than 6a mesh or terial containing gold with a range of size radiotracer technique for evaluating grav­ 25a microns, but also coarser gold with and shape characteristics. In order to be ity concentrators. The technique has been a low shape factor that may decrease its prepared for the resurgence of interest successfully applied to a detailed investi­ recovery by conventional, large-scale in fine gold concentrators which will gation of the compound water cyclone sluicing operations. All sieve designations surely follow the next upturn in gold (Fig. 1 ), an enhanced gravity concentra-

Daniel E. Walsh is a mining engineer and instructor with the Mineral Industry Research Laboratory (MIRL) of the University of Alaska-Fairbanks. He has recently completed his master's thesis in mineral preparation engineering at UAF. Mr. Walsh designed the radiotracer technique as applied to placer gold recovery evaluation and has used it successfully in his research.

The Northern Engineer, Vol.17, No.2 13 tor for the beneficiation of slurries of vious if we consider, for example, MIRL's finely divided materials.3• 4 Then, on the average, one would expect a compound water cyclone (CWC) evalua­ Gravity concentrators are evaluated 3000-gram sample to contain 10 mg of tion procedure as it was prior to the de- either in closed or open circuit. The pro­ gold, or about one fairly flaky 10 X 20 cess developed by M I R L employs neutron­ (1.7 X 0.8 mm) mesh gold grain. If the activated gold (tea Au) and radiation grain is lost in the overflow, does this mean detection circuits that monitor the con­ the CWC's gold recovery is zero? Should r---~----~41NeH centrator's product pulp streams. Con­ it be recovered, can the investigator claim centrator recovery is determined from the ewe 100% recovery? Of course the answer to ratio of the number of particles detected these questions is both yes and no. Based passing into the concentrate to the total on the results of this one very limited test, number of particles detected over all the yes; but from a common sense and scien­ monitored pulp streams. This system elim­ SAMPLE tific viewpoint, the test is meaningless. inates the experimental errors introduced What would be preferable? One answer by sampling, sample reduction, and as­ SAMPLE would be to salt the sample with a large saying and allows recovery to be evaluated number of gold particles of similar size for gold particles of specific sizes, shapes, and shape, sample the products, and SUMP and fineness. In addition to allowing for a determine their gold content. This is a more accurate and detailed recovery reasonable approach until the amount of analysis, the process reduces the time re­ work in sample reduction and assaying is quired for unit evaluation when compared considered, along with the experimental to other recovery analysis procedures. error introduced. Also, the gold recovery Though this technique was developed for of the ewe would be evaluated only for application to gold recovery systems, it PUMP those few seconds for which its products were sampled. may be extendable to the study of other Figure 2. Conventional closed-circuit minerals and to other physical processes gravity concentrator evaluation system Another solution would be to run a used by MIRL. involving mineral grains. large amount of material through the system in open circuit. But again one is RATIONALE FOR THE TECHNIQUE faced with spending much time in sample velopment of the radiotracer technique. reduction and possibly going through The recovery of most minerals that are Suppose a placer gold sample is to be reconcentration stages that will introduce amenable to gravity concentration is usu­ processed by a 4-inch compound water their own error into the process. ally determined by accurate sampling and cyclone in a laboratory assaying. For particulate gold, sampling closed- circuit operation and assaying are still the convention, but (Fig. 2). Past laboratory the accuracy and reproducibility of these practice would dictate al­ operations are much discussed and de­ lowing the system to reach bated points. Evaluating the performance operating stability, sampling of gravity concentrators by conventional the overnow and underflow sampling and assaying techniques there­ streams simultaneously for fore is not only very time-consuming and 2 to 5 seconds, then dis­ costly, it may also give uncertain results. mantling the cyclone to In gold placers, where grades of 0.01 clean out any trapped gold, 3 3 oz/yd (407 mg/m ) are common, pri­ not to mention all the pos­ mary concentration products collected in sible gold traps existing in the field may require significant upgrad­ the system's plumbing. ing in the laboratory before sampling and Let's assume we want a assaying can be done. Each subsequent ewe feed pulp density of concentration introduces its own recov­ 10%. For MIRL's system, ery error into the overall evaluation pro­ this required a -4 mesh cess, and often the researcher wonders (4.8 mm) solids charge of how meaningful the back-calculated pri­ approximately 3000 grams. mary stage recovery values are. Similarly, Let's also assume that our closed-circuit laboratory testing of run­ -4 mesh material has a rela­ of-pit placer sands, which generally con­ tively high grade of 0.1 tain so little gold that only a few small oz/ton (3429 mg/tonne). grains of gold distinguish the concentrate from the tailings, makes the wisdom of Overflow (right) and underflow product sampling highly suspect. These (left) detection chambers of problems are not unique for placer gold MIRL'sradiotracertest system. ores and apply to any low-grade ore with The CWC is positioned above particulate values. the underflow detection cham­ ber. Irradiated gold particles The rationale for applying radiotracer are introduced to the system techniques to this problem becomes ob­ through the white funnel.

14 The Northern Engineer, Vol. 17, No.2 A plastic pipe dry well houses erned by a binomial probability distri· the thallium-activated sodium bution. iodide scintillation detector. A property of the binomial distribu­ The concentrator slurry prod.· tion is that it has mean (1-!) equal to uct passes around the dry well. P, where P is the probability of the suc­ The slurry is confined by the 2 surrounding steel pipe of the cess of an event. The variance (u ) is detection chambers. equal to P(Q) where 0=(1-P); Q is the probability of failure of an event. In the present context, the event in question is test results. This is also true the recovery of a gold particle. Thus, P because the concentration equals the probability that a particle is performance is observed recovered. over a longer period of The number of observations n that a time, typically 10 to 30 researcher must make to estimate P de· minutes, compared to the pends on the degree of accuracy desired. 2 to 5 seconds of sampling We specify the estimate of P as p and time. state that P lies in the interval p ± E with Using the radiotracer a level of significance a, where (1-a) technique allows the recov­ indicates the percentage of the time when ery of particular sizes and our estimate would be correct. The more flatnesses of gold to be observations we make, the greater confi· studied. This system is dence we have in our estimates of the most useful when a large true recovery of the concentrator. The number of tests are to be number of observations required to esti· run in order to evaluate a mate an interval containing P (p ± E) with concentrator in a variety a level of significance a is given by: 5 of settings (i.e., factorial n = [Z(a/2)] 2 p(q) designs), and allows accur­ (1) ate testing of concentrators (E)2 operated in closed-circuit where: systems. n = required number of observations Z(a/2) = standard normal score of (a/2) The new evaluation process employs STATISTICS OF THE p = the estimate of P native placer gold particles that have been RADIOTRACER TECHNIQUE q = 1- p activated in a nuclear reactor. When irradi­ E =maximum error of estimate ated in a reactor, gold absorbs neutrons. With the radiotracer technique, a par­ The value of n for a specific E and Having absorbed a neutron, a gold atom is ticle is either recovered in the concentrate Z(a/2) is maximum when p = q = 0.5 unstable and decays, giving off a charac­ or lost to the unit's other pulp streams. (50%). More observations are required for teristic high-energy gamma radiation Because a particle therefore follows one estimates of P when P is near 50% than which can now be detected. In the MI R L of two possible courses, the distribution system, gamma detectors are coupled to of the concentrator's recoveries is gov­ for larger or smaller values of P. electronics which connect to a strip chart recorder, giving a hard-copy record of gold particle passage via either the overflow or underflow product, from which gold recovery may be calculated .------...... 4 INCH easily (Fig. 3). ewe This system has many advantages. ELECTRONICS First, it saves time. No product sampling, sample reduction, or assaying are re­ quired. Rather than performing the more UNDERFLOW OVERFLOW tedious laboratory work, the researcher DETECTION DETECTION has more time to run tests and analyze re­ CHAMBER CHAMBER sults. As a case in point, ewe evaluation by radiotracer techniques has allowed as many as 100 tests to be run at the cost of only 30 man-hours. More typically, each recovery test involves approximately 3 CHART man-hours, compared to 8 or 10 man­ RECORDER hours for conventional sampling/assay­ ing evaluation procedures. Because the intermediate steps of PUMP sampling and assaying are removed, this process allows greater confidence in the Figure 3. Closed-circuit radiotracer evaluation system for Ml RL's CWC.

15 The Northern Engineer, Vol. 17, No.2 Since in the present system the pulses sions can be made from hand calculations 2 detected from the mineral particles give a n = [Z(a/2)] p(q) or prepared tables. (E)2 constantly revised estimate of P, the value = (1.96F p(q) of n may be computed by Equation 1. TYPICAL APPLICATIONS When the actual number of total particles (0.05F detected equals n, the test is considered The first of the two examples follow­ = 1536 p(q) (2) complete. ing describes part of a project completed by the author as a master's thesis. As a Each test was begun by charging the system with water and solids and adding PREFERRED FORM result of this work, much detailed infor­ mation now exists concerning the gold re­ from four to eight activated gold parti­ The technique is most useful when a covery and other characteristics of the cles. As the gold particles were processed large number of tests are run to evaluate 4-inch CWC. This information is pres­ through the compound water cyclone the recovery of a concentrator. Figure 3 ently avai !able through MI R L. The sec­ they were either recovered into the un­ shows the preferred experimental system ond example describes a project funded derflow pulp stream or lost to the tail­ ings in the overflow pulp stream. As a where the concentrator is evaluated in by the U.S. Bureau of Mines that MI R L particle exited the cyclone body via closed circuit. Radioactive mineral grains will begin in the fall of 1985. are introduced to the system where they either product, it was detected by a are recirculated, making many transits Example 1 2-inch diameter by 2-inch long thallium­ activated sodium iodide scintillation through the concentrator and having MI R L wanted to evaluate the ability counter coupled to measurement elec­ a probability P of being recovered on of the CWC to recover fine placer gold. In tronics, which were connected to a dual each passage. In this design, a limited one phase of this study, an experiment pen strip chart recorder. One pen recorded number of mineral grains may be used. was designed to determine the effects of particle passages through the overflow Where the system is evaluated using an three factors on the cyclone's gold re­ (tailings); the other pen monitored the open circuit design, n particles would covery: (1) the top size of the feed, (2) underflow detector. be required. the presence or absence of heavy minerals The preferred detection system con­ in the feed, and (3) the amount of -400 Once the system was functioning, a sists of suitable gamma ray detectors mesh (37 microns) slimes in the feed. A minimum of 100 observations were made. (G-M tubes, scintillators, semiconductors, complete factorial experiment was de­ A percent recovery value, p, was then cal­ etc.) housed in chambers through which signed, using a fixed-effects analysis of culated based on these initial observations. the concentrator's pulp streams pass. variance model for data analysis. The This value of p was used in Equation 2 to Measurement electronics - preamplifiers, tests were run using gold particles of 35X calculate a value for n. If n was less than amplifiers, discriminators, and rate meters 48 mesh (420 X 297 microns) with a flat­ or equal to 100, the test was considered - are connected to the detectors. The ness described by Corey's Shape Factor6 complete. However, if the calculated n rate meter output drives either a counter, as 0.15 X 0.05. (Corey's Shape Factor = was greater than 100, the test was contin­ strip chart recorder, or computer soft­ C/VAB, where A = particle length, B = ued until n(n 0) observations were com­ ware to give the counts per detector. particle width, and C = particle thickness.) pleted and a new value of p determined Where a computer is incorporated into In this series of tests it was desired to from the chart recorder output. Again, a the design, a program may be written to make gold recovery estimates of p ± 5% new n (n') would be computed. This pro­ update the value of n continuously and at a 90% confidence level (a= 0.1, Z(a/2) cess continued until n' was less than or to signal when the test has been completed. = 1.96). This required n observations as equal to n0 , yielding the desired degree of If a computer is unavailable, these deci­ calculated from Equation 1: accuracy to the estimate of P by p. The data from this experimental phase are shown in Table 1. Some points of interest concerning Table 1 are: • Each treatment cell contains two repli­ cates. Table 1. Gold Recovery (%) Using the CWC • The experimental error (MSE) indi­ cated by an analysis of variance of the Low -400 Mesh Slimes High -400 Mesh Slimes data was 0.00073, which yields an E of (5,000 mg/1) (15,000 mg/1) 0.053 (5.3%) at a = 0.1. (Recall that the Top Size With Heavy Without With Heavy Without desired E was 5%.) of Feed Minerals Heavy Minerals Minerals Heavy Minerals • The 24 tests of the experiment were completed in 12 man-hours; for such test 4 Mesh 82.1 79.0 84.8 78.8 work, this was a very rapid evaluation. 84.5 82.9 86.8 84.5 The advantages of using neutron­ 10 Mesh 87.7 84.5 83.8 86.2 activated placer gold particles become 84.4 86.4 90.9 86.6 apparent, considering certain facts: 28 Mesh 94.8 91.3 91.8 92.8 • The recovery of a particular size and 97.0 97.0 93.6 97.0 shape of gold is deducible under run-of­ pit grade conditions, in closed circuit Note: Each treatment cell has two replicates. operation. • The recovery is obtained (calculated) ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~-over a long period of time, ~lowing for

16 The Northern Engineer, Vol. 17, No.2 perturbations of the cyclone's bed, flow RETURN patterns, etc. • Neither sampling nor assaying of the products is required. Recovery is calcu­ lated by simple summation and division. HEAD TANK 0 • The accuracy of the test is predictable 0 < w PARTICLE m from the number of gold transit cycles w XI LL.. INTRODUCTION ., observed. r • Depending on the recovery range one is ~ 0 ~ observing, test lengths may vary from 10 minutes to an hour. These shorter total VALVE test times allow the researcher to run a greater number of tests. • The experimental error is considerably PUMP RETURN TANK reduced, allowing for greater power in \;DETECTION SLIT statistical conclusions. t FLOW METER Yo DETECTION Example 2 "'T ~~-______, ELECTRONICS MI R L proposes to study the settling velocity of fine free gold particles as a •• ,. SHIELNG\ DETECTORS function of the total suspended solids in the water medium. Previous work on gold J D lcl: /,_ ___ settling velocity has been done by other .----: researchers as has work with the settling I &ETECTION SLIT I 7 10 CHART I velocity of other minerals. - All of 6 RECORDER these studies, however, used optical a 6 measurement methods which restricted PERSONAL COMPUTER them to fairly coarse sizes of gold ( ~ 2 mg) and to clear water conditions. The proposed work removes both of these PARTICLE restrictions, thanks to the radiotracer RECOVERY FLASK technique. This technique has been used to detect gold having a mass of approxi­ Figure 4. Settling velocity measurement system employing radiotracer techniques. mately 0.1 Mg. As can be seen from Figure 4, the Annual Conference on Alaskan Placer Min­ as a function of several factors: gold size, shielded scintillators now monitor the ing, Fairbanks, AK. gold shape (flatness). gold fineness (speci­ settling column through detection slits at 4 Walsh, D. 1985. Evaluation of the 4-inch Com­ fic gravity). water temperature, suspended heights h and h .The distance between pound Water Cyclone as a Fine Gold Con­ 1 2 solids concentration, and suspended solids centrator Using Radiotracer Techniques. the detection slits is designated ~h. Water mineralogy. Both native placer gold of Master's Thesis, University of Alaska-Fair­ is fed to the base of the settling column various sizes and shapes and synthetic banks. 268 pp. from a head tank at a flow rate 0, which gold particles manufactured to size, shape, 5 Johnson, R. 1976. Elementary Statistics. is measured by the circuit's flowmeter. and density specifications will be studied. Duxbury Press, North Scituate, MA. 550 pp. For a settling column with inside dia­ It is anticipated that the use of synthetic 6 Corey, A. T. 1949. Influence of Shape on the meter D the upward flow velocity (V l of 0 gold grains of known characteristics will Fall Velocity of Sand Grains. Unpublished the water is given by: Master's Thesis, Colorado A and M College allow researchers to draw conclusions as (now Colorado State University), Fort Col­ = 4(0)/?r D2 (3) v0 to the applicability of fluid mechanical lins, CO. 102 pp. Radioactive gold introduced through the settling laws (Newtonian, Stokes, and 7 Saks, S. Ye. 1975. Principles of hydrodynamic funnel at the top of the settling column transitional) to predict the settling velo­ equivalence of clastic particles. International will reach its equilibrium settling velocity city of gold grains. Geology Review 18(5):541-644. above h and continue to settle past the 8 Shilo, N. A., and Yu. U. Shumilov. 1970. New 1 experimental data on settling of gold parti­ detectors, settling through the distance cles in water. Doklady Akademii, Nauk, ~h in a time period t. The settling veloci­ REFERENCES SSSR 195(1):193-196. ty of the gold is then given by equation 4. 1Guest, R. 1980. A Survey of the Literature on 9 Shumilov, Yu. U., and A. G. Shumovskiy. Gravity Separation. South African National 1975. Experimental data on the hydraulic Vs ~h/t + v0 Institute of Metallurgy, Report No. 2082. size of some placer minerals in the northeast ~h/t + 4(0)/?r D2 Randburg, South Africa. USSR. Doklady Akademii, Nauk, SSSR 225(5): 1174-1176. (4) 2 Cyclone Engineering Sales Ltd. 1978. Com­ c,/t + c2 (Ol 10Tourtelot, H. A. 1968. Hydraulic Equivalence pound Water Cyclone Manual No. 4-1. Ed­ C and C are system constants. C1 of Grains of Quartz and Heavier Minerals 1 2 monton, Alberta, Canada. 24 pp. equals the distance ~h between detectors and Implications for the Study of Placers. 2 3 Geological Survey Professional Paper 594-F. and C is equal to the quantity 4/rr (D) • Walsh, D. 1985. Evaluation of the 4-inch Com­ 2 U.S. Government Printing Office, Washing­ The system shown in Figure 4 will be pound Water Cyclone Using Radiotracer Techniques. Paper presented at the Seventh ton, D.C. 13 pp. + used to study the settling velocity of gold 17 The Northern Engineer, Vol. 17, No.2 Monitoring Temperatures in an Offshore Arctic Well: A Brief Note

by Alan Taylor and Alan Judge

In early May 1985, a multithermistor cells sufficient for several years' operation. cable and data acquisition system was in· The data acquisition unit left on the sea stalled in Panarctic Oils' exploratory off. ice uses bubble memory and is housed in shore well, Cape Allison C-47, shortly a heated, insulated environmental con· before the well was to be abandoned. The tainer. well is located in 250m of water between Since the system was installed, the site Ellef Ringnes and King Christian islands has been visited twice to recover data. in the Sverdrup Basin, Canadian Arctic Temperature profiles measured over the Islands. The sea-floor package is measuring first week illustrate the cooling of the temperatures to an accuracy of 0.01 K six well from the heat produced by the dril· times a day over the upper 800 m of the ling and testing procedures. Already, two well and transmitting the data acoustically distinct temperature gradients are emerg· through the water to a recorder left on ing; it is thought that these are a reflection the sea ice. At this High Arctic interisland of a major lithologic change around 500 location, sea ice rarely drifts more than a m below the sea floor. few hundred meters a season; the range of The deployment of this system culm· the system is tolerant to drifts of up to 2 inated several years' planning by the Earth km before data is lost. The experiment is Physics Branch of Energy, Mines and Re· planned to last for a couple of years, with sources Canada (EMR) and by Panarctic the surface recorder removed only during Oils Ltd. The data now being recorded by the brief open-water season. the automated system will complement The multithermistor cable is instru· the permafrost temperature data gathered mented with 13 thermistors and connect· by the Earth Physics Branch at over 100 ed to an electronics package positioned in onshore exploratory wells during the past a special casing adaptor at the sea floor. 20 years. The data will be of use to engi· The subsea unit is powered by lithium neers in understanding the well thermal

A propane-heated container left on the sea ice houses the surface telemetry unit and recorder. Dr. Alan Judge is a research scientist with the Canadian Department of Energy, This unit is visited periodically to recover the Mines, and Resources, and leads a northern research group. Alan Taylor is a geophys· data and is removed only during the brief open· icist in the same group. Both have been involved in permafrost studies and applied re· water season. search in northern geotechnical subjects for a number of years.

18 The Northern Engineer, Vol. 17, No. 2 5 10 15

CAPE ALLISON C- 47 77° 46.1'N 100°f7.3'W s regimes and in designing production Cl w programs. CD <[ This is believed to be the first time w (/) that a temperature cable and automatic 3:400 recording system have been installed in an 0 ....J abandoned offshore well. The data acqui­ w sition system was built by Mesotech CD J: Systems Ltd. of Port Coquitlam, British li: Columbia. Dobrocky SEATECH, Sidney, w British Columbia, were project managers. Cl Further information may be obtained ~T = 23mK/m from the authors at Earth Physics, EMR, ~z 1 Observatory Crescent, Ottawa, Ontario K1A OY3; Denis Baudais, Panarctic Oils BOO Ltd., P.O. Box 190, Calgary, Alberta T2P 2H6; or Mark Hill, Dobrocky SEA TECH., This figure shows the range of the first week of temperature data obtained from the installation. The cooling appears most rapid in the upper several hundred meters; the Box 6500, Sidney, British Columbia, VSL two distinct temperature gradients suggest a major change in lithology around 500 m. 4M7. + The location of the well in the Canadian Arctic Islands is shown in the inset.

'\.1/ MESOTECH 612 Depth -0­ Surface Stn. (m) /71~ And Housing 0 :~~~'. •I' 1111 ~~~~:· ....\\\0 .~ 1"''•''::•\\:uf,IUI,I\'I''',, II';,~·'' ~pi,,...

:: :;.Q~ :::::::::::"':'.-!:':1-1.. :::::~.::· 100 ::::: p~~~. :c~P.tlJ.r.~ e/.o) :.

:::.:•:::::::::::::::~~:::: ...... ·...... :::::•:::::::::::::::;:.~: MESOTECH 532::::· :::Telemetry:Unif:::: ·•

3 2 1 Distance (km) 1 2 3

Schematic diagram of the automatic data acquisition system installed in an abandoned offshore petroleum exploration well in 250m of water, in the Arctic Islands of Canada. The subsea telemetry unit scans the thermistors on the 800-m cable six times a day and acoustically transmits the data through the water to the recording package left on the sea ice. More than 2 km of ice drift can occur before a degradation in data capture occurs.

The Northern Engineer, Vol. 17, No.2 19 DIARY OF A CHEECHAKO BUILDER by Ken L. Larson

ONcE THE JNITIALexcitementofthe of the local environment before making first call, job offer, and acceptance of a the economic determination in April1984 position in Fairbanks, Alaska, has worn off that I could get more home for the money (which, in my case, began as I stepped out by building one. This decision then re­ of the airport terminal to meet a temper­ quired the selection of a site, a design, ature of-40°F). a newcomer (cheechako) and a builder. Again, a lot of legwork and must take a serious look at just living in a discussion with experienced local people subarctic environment. It matters not how was required. I had not yet attended any well-prepared one is or how good the job arctic construction courses, and knew my or working conditions may be; having a Oregon experiences would not translate well-built, economical-to-operate and rela­ automatically to Alaska circumstances. tively maintenance-free dwelling to come I received a lot of advice on what to home to is a must, especially where a fami­ consider when building a home near the ly must spend long, dark winter hours in­ Arctic, mostly oriented toward the cost side. The task of selecting or building a of heating during the long winters. This home here is not one to be entered into advice included: (1) choosing a site on lightly, either by a nontechnically minded high ground for higher winter tempera­ individual or even by a seasoned engineer tures and fewer floods; (2) choosing a site who lacks arctic experience. without permafrost, which is easier said That I survived this trial-by-fire home than done (my advisors told me to look building endeavor from December 1983 first for big trees, but since these are only through November 1984 primarily was due an indicator, ice-free conditions should be to my common-sense construction back­ verified by exploratory drilling); (3) stay­ ground and use of engineering logic, cou­ ing with a basic box structure in order to pled with lots of local advice, and a lot of minimize exposed surface area; (4) orient­ luck. ing the structure to the south and using triple-pane windows kept to a minimum SITE SELECTION surface area; (5) using a vapor barrier of 4-to 6-mil polyethylene sheeting on the A buy-or-build determination must be inside (warm side) of all exterior walls made when acquiring a home, primarily and ceilings; (6) not using double-sheathed influenced by finances and modified by construction with 15-pound felt paper on such conditions as (1) the availability of the outside of the exterior walls, since already-built houses that will withstand they need to "breathe"; or (7) using 15­ scrutiny for their cold climate suitability; pound felt paper over sheathing that has (2) the availability of builders with local all stud cavities drilled with 1-inch diam­ experience who have been around for at eter holes, top and bottom, for venting least five years (which is about how long moisture to the exterior; (8) not insulating it takes a permafrost thaw bulb to cause floors above a crawl space, but using a damage); (3) the desired amenities and heated crawl space instead to prevent pipe surroundings of the home; (4) the desired freezing; and other considerations. Among location and proximity to work and so­ the advisors, I tended to rely more on the cial activities; (5) the time of year; (6) builders with longevity and a history of resale possibilities; and finally, (7) how satisfied home owners than on some less­ long one can live out of suitcases or how experienced people who suggested state­ soon the family will arrive. of-the-art "breakthroughs." Keeping the above considerations and Finally, due to perseverance and a fair a budget in mind, I spent several months amount of luck (and pressed by the fam­ talking to realtors and seasoned veterans ily's arrival), I had put together a budget,

Ken L Larson is the Resident Engineer for the U.S. Army Corps of Engineers in Fairbanks, Alaska. He is registered as a professional civil engineer in the states of Oregon and Washington, and is pursuing CE registration in Alaska. Mr. Larson resides with his wife and two children in the now-finished home in Nonh Pole described in this article.

20 The Northern Engineer, Vol. 17, No.2 a builder, and a design by the end of June table was located 8 to 9 feet below the finish slab grade. At that point, I hand­ 1984. Despite my logical, engineered ap­ original ground surface and roughly cor­ placed a special section of backfill under proach, the selection of the exact site was responded to the level of the Chena River. the garage and the south -facing "solar totally one of chance-it was the last one Later on, during unusually high water on room" slabs. Six-mil polyethylene sheet­ for sale by the chosen builder in the de­ the Chena in early August 1984, the water ing was placed over the backfill gravel and sired residential area. The lot previously table observed in the excavation for the was covered with 2 inches of extruded had been cleared and excavated so that I home's fuel oil tank was about 7 to 8 feet polystyrene rigid insulation. The 6-mil could examine the soil conditions for per­ below the original ground surface. polyethylene sheeting was used to inhibit mafrost. When I bought the lot, I also de­ The builder previously had constructed degradation of the insulation and to cided to use a video cassette recorder to homes in this area and had achieved good prevent moisture transfer through the keep track of progress throughout the results with excavating unsuitable frost­ slab. The insulation was then backfilled construction period. susceptible materials and replacing them with about 10 inches of hand-picked 1 '!:z­ inch-minus pit-run gravel containing a FOUNDATION AND CONCRETE with compacted 3-inch-minus pit-run grav­ el as preparation for a firm foundation continuous coil of polybutylene pipe, The site is on the Tanana River's 100­ in the active (seasonal) frost layer. 510 feet long and % inch in diameter to 500-year flood plain, southeast of Fair­ (Fig. 2); the fill was then plate compact­ banks and close to the Chena River. In After I examined the foundation site, ed. Water from the oil-fired boiler will be fact, the home site is directly atop an old the builder backfilled with nonfrost­ circulated through the pipe to heat the Chena River meander channel, which one susceptible gravel and then vibratory-roller slab. of my advisors had suggested might be compacted the site to within four feet of The performance of this special section less likely to be underlain by permafrost. the final grade. The reinforced concrete remains to be evaluated, but I found out The site was heavily wooded with birch foundation footing and walls were then why it would be expensive to install com­ and spruce trees up to 6 inches in diam­ placed on the prepared foundation. The mercially. Placing approximately 20 cubic eter. However, other than indications from exterior of the foundation walls was also yards of gravel by hand is not easy or fun! previous water well drilling operations, no waterproofed with asphalt emulsion, cov­ (I was willing to undertake the extra ef­ bore log data was available to establish ered with 2 inches ( R-11) of rigid poly­ fort and expense because among my the presence or absence of permafrost at styrene insulation, sheeted with 6-mil limited "arctic" experiences was that of the fqundation site. polyethylene, and then backfilled with repairing a vehicle during January. The The foundation had been excavated the excavated sandy silt (Fig. 1 ). The in­ garage air temperature was 65° F four feet in the old meander channel depression terior concrete walls and gravel floor of above the floor, but the slab temperature early in June 1984, after spring breakup, the crawl space were later covered with was -30°F-and I was lying on that slab and 9 to 13 feet of frost-susceptible soils 6-mil polyethylene after the home was under the car. That memory kept my (mostly sandy silt) had been removed sealed in and mostly finished. shovel moving.) down to unfrozen sandy gravel, which The garage foundation walls were con­ Problems gave good indication of being below the structed in the same manner but were freeze-thaw active layer. When I first ex­ backfilled with compacted 3-inch-minus A problem with the home foundation amined the site in mid-June, the water pit-run gravel to within 16 inches of the did occur in late July 1984, after two 2" 6" FIGURE 1 -~~{~ 6-MIL POLYETHYLENE SHEETING 2" (R-11) EXTRUDED SANDY SILT POLYSTYRENE RIGID INSULATION BACKFILL ASPHALT EMULSION DAMPPROOFING +4 STEEL REINFORCED CONCRETE 9'-13' OF SANDY SILT 6-MIL POLYETHYLENE (SEASONAL FROST ZONE) SHEETING IN CRAWL SPACE ~~~~~~~~---t 3"-MINUS PIT-RUN SANDY GRAVEL BACKFILL -+------=~...._._,_.~~~--! UNFROZEN SANDY GRAVEL t TYPICAL FOUNDATION SECTION

The Northern Engineer, Vol. 17, No.2 21 prolonged periods of heavy rain (each approximately one week long, with one week of drying in between). During one of my daily "quality· control" inspection trips, I discovered that the gravel FIGURE 3 backfill had subsided approxi­ mately 2 inches out from under the southeast corner of the concrete for a distance of about 16 feet. In addition, the foundation wall had de­ SEASONAL FROST ZONE veloped cracks and had settled {ACTIVE LAYER) about 1Y, inches. A review of the previously recorded video­ SANDY SILT tapes indicated the probable cause of the problem: the southeast corner of the foot­ t ing was apparently underlain UNFROZEN SANDY GRAVEL by a thin wedge of frozen ' sandy silt that was contained t SOUTHEAST CORNER FOUNDATION SUBSIDENCE between the naturally occur­ ring unfrozen sandy gravel and the 3-inch-minus pit-run gravel backfill. September 1984, after the house fram­ WELL DRILLING AND WATER This thin wedge of frozen sandy silt ap­ ing was completed but before the sheet­ SYSTEM parently was left as a result of the natural rock was installed, the floor joist mud slope lay-back in a corner of the excava­ plate over the settled southeast corner The well was located inside the heated tion site. When the frozen material melted was wedged back to grade and subse­ garage, which is at least 100 feet from the and was subjected to runoff from both quently dry-packed with grout. The suc­ septic tank, primarily because the water the groundwater and surface water, some cess of this correction remains to be seen table is high enough to use a less expensive, of the now-thawed sandy silt washed away, during annual freeze-thaw cycles. The low-maintenance suction pump placed permitting the remainder to consolidate builder has agreed in writing to be respon­ above ground. In addition, the well loca­ and subside (Fig. 3). sible for further damage or corrections for tion made for a short water line, and the The correction of this subsidence prob­ five years hence. well is readily accessible during the winter lem involved the mini-excavation from in­ A potential problem may exist for frost months. side the crawl space of an 8-inch deep heaving of the 1000-gallon oil tank be­ The well was driven on 17 July 1984 section of backfill below the concrete cause it lies in the active frost layer and to a depth of 84 feet, using a 4-inch diam­ footing, approximately 16 feet long and is close to the water table. However, eter steel casing with churn drill assist. No 42 inches wide (including the full 16-inch when it was installed, a 2-inch layer (R-11) apparent permafrost or ice was encoun­ width of the existing footing). This mini­ of rigid polystyrene insulation was placed tered. The wells in the two adjacent lots excavation was then filled to excess from immediately above the tank and covered (north and south, less than 175 feet away) inside the foundation wall with approxi­ with 6-mil polyethylene sheeting in order were driven to depths of 52 and 72 feet mately two cubic yards of concrete (Fig. to slow down the ground's freezing and in May and June of 1984; permafrost was 4). A surveyor's level was then used to lessen or possibly arrest the frost heave encountered in both cases. The presence monitor any further settling of the foun­ action. This will be monitored for its of permafrost was confirmed in late Au­ dation wall; no more occurred. In late effectiveness. gust when both had to be thawed for

FIGURE 2 4" CONCRETE SLAB, WOVEN WIRE FABRIC REINFORCED 1 112"-MINUS PIT-RUN SANDY GRAVEL BACKFILL l'?tj~~~=-- 3/4"-DIAM. POL YBUTYLENE PIPE ·If HEATING COIL, 16" ON CENTER 2" (R-11) EXTRUDED POLYSTYRENE RIGID INSULATION 6-MIL POLYETHYLENE SHEETING 3"-MINUS PIT-RUN SANDY GRAVEL BACKFILL

GARAGE AND SOLAR ROOM SLAB - SPECIAL HEATING SECTION

22 The Northern Engineer, Vol. 17, No.2 The 56-foot run of 4-inch­ diameter ABS drain line be­ tween the home and the septic tank was wrapped with a switch-controlled heat trace to prevent its freezing, a possi­ bility because of its relatively shallow 3- or 4-foot depth. FIGURE 4 In addition, the line was :._ slightly humped to avoid a SANDY SILT •. BACKFILL freezing-vulnerable low spot in the middle of the run, bed­ SEASONAL FROST ZONE ded in gravel, and covered (ACTIVE LAYER) with a 24-inch width of hori­ zontally placed 2-inch-thick SANDY SILT polystyrene rigid insulation wrapped in 6-mil polyethylene sheeting. The backfill was t completed with the excavated UNFROZEN SANDY GRAVEL sandy silt (Fig. 5).

t SOUTHEAST CORNER FOUNDATION SUBSIDENCE REPAIR Problems The most obvious problem with sewage systems because suction pipe and heat trace (heat tape) in­ 9 or 10 feet, where frozen gravels and a of low winter temperatures is the low rate stallation. My well has been ice-free so rising water table were encountered. It of decomposition in the septic tank. When far, but a heat trace was installed just in was my opinion that the frozen gravels this is coupled with frozen leach fields in case it is ever needed. were not permafrost, but rather were the the winter, the net result is that the septic The home's interior water piping and result of snow and seasonally frozen soil tank will need to be pumped out at least plumbing are conventional except that being covered over during backfilling early every two or three years. they are installed on inside walls and in a in the construction season. However, the Another problem that low winter heated crawl space. The cold water piping tank was buried at a depth of 4 feet. The temperatures cause for sewage systems is is also insulated to prevent condensation, leach line, approximately 110 linear feet possible displacement of the drain line since the well water is extremely cold of 4-inch diameter perforated acrylonitrite and septic tank, due to either settling (34° to 35°F). Frost-proof faucets were butadiene styrene (ABS) piping, was bur­ from the creation of a thaw bulb in per­ used for hose bibs on the home's exterior. ied about 7 feet deep in 1 foot of filter­ mafrost or to heaving of the drain line or cloth-covered 2-inch drain rock over 1 septic tank caused by the action of sea­ SEWAGE DISPOSAL SYSTEM foot of 6-inch-minus talus rock. The tank sonal frost. The results are the same: The 1300-gallon septic tank had to be top and sides were then covered with 2 broken lines and connections or low spots located at least 100 feet from the domes­ inches ( R-11) of extruded polystyrene in the line or a tipped tank, any of which tic water well, which placed it approxi­ rigid insulation, sheeted with 6-mil poly­ means the sewage no longer flows where mately 56 feet east of the home and along ethylene, and then backfilled along with it should. the old meander channel line. Excavation the leach field with 1 to 2 feet of 3-inch­ I have tried to prepare for these prob­ for the septic tank and leach field was minus pit-run gravel, topped off with the lems, and for freezing by putting a heat made in mid-August 1984 to a depth of excavated sandy silt. trace on the drain line, but only time will

FIGURE 5

--;AND~SIL~ACKFI~ ~----- 3'-4' BURIAL

SANDY SILT 3"-MINUS PIT-RUN SANDY GRAVEL 6-MIL POLYETHYLENE SHEETING ~~~~~~~::___ 2" (R-11) EXTRUDED POLYSTYRENE RIGID INSULATION 4" DIAM. ABS SEWER DRAIN LINE SWITCH-CONTROLLED HEAT TRACE SEPTIC TANK DRAIN LINE PROTECTION

The Northern Engineer, Vol. 17, No.2 23 tell how successful my efforts have been. causing leaks into the attic. I was warned­ I suspect that the best advice I received and I heeded-that one must watch out is to expect problems-inevitably-with for excessive use of humidifiers in rooms the sewage system. that are vapor-barrier tight to prevent a large vapor loss to the attic, which might HOUSE CONSTRUCTION lead to ice formation in the insulation. My advisors offered a myriad of sug­ Silicone sealant should be used to caulk gestions as to the "best" way to build an around all ceiling penetrations. arctic-worthy home. Most of these sugges­ saves snow shovelling and provides easily tions were apparently sound, but were accessible sheltered firewood storage. CONCLUSIONS AND FUTURE definitely subject to the amount of cash • Cement pavers (2ft x 2ft x 6 in) were POSSIBILITIES available and level of personal amenities used in lieu of poured concrete sidewalks Construction of a house appropriate desired. The common thread contained in and patio to allow for readjustments in for a subarctic environment is not impos­ most suggestions pertained to conserving case of frost heaving. sible-just unusual. There are a lot of heat as efficiently and economically as items that must be considered and accom­ possible, and involved the use of a tight • Two airtight wood stoves provide sup­ plished correctly in order to complete a vapor barrier with as much insulation as I plementary home and water heating. well-built, economical-to-operate, and rel­ could afford. Avoiding extremes but with • A quart-size instant hot water heater atively maintenance-free dwelling suitable that basic advice in mind, I discussed at the kitchen sink provides small quanti­ for interior Alaska. I could have saved heating costs, insulation, and construc­ ties of hot water. myself considerable time had I been able tion techniques with numerous people • All bath, kitchen, and laundry vents to attend an arctic engineering or con­ before deciding to use 10-inch thick are run through the walls instead of the struction course initially, but I could also fiberglass insulation in double-wall con­ roof in order to conserve heat. The air­ rely on others' experience and use a well­ struction, laid out in a single-story floor tight wood stoves also have P-trap type established local builder to get through plan. fresh air supplies, loosely stuffed with in­ the process with a minimum of problems. Although windows and doors with sulation, installed through the walls. windows are great heat wasters when com­ This report on the house-building pro­ pared to 10-inch thick walls, they are • All floor sheathing is glued to the floor cess reflects the difference between what still desirable from both a social and joists to prevent its moving in response to I knew already, as a practicing engineer psychological point of view. The place­ temperature and humidity extremes in elsewhere, and what I had to learn. "Frost ment of these necessary openings in my the changing seasons. heave" was barely an item in my vocab­ ulary, much less "permafrost," and these home was based on personal preferences • Meticulous attention was given to the exotic hazards dominated my concerns rather than energy efficiency, with the installation and lapping of the 6-mil poly­ as they do this article. idea that some compensating features ethylene vapor barrier behind the sheet­ could be incorporated into the home de­ rock. All electrical box, wiring, and piping Some thoughts and other ideas that I sign and operation. penetrations were sealed with silicone intend to pursue in the future: Some of the compensating features sealant in walls, ceilings, and floors, and 1) For my own interest, and because include: around all door and window frames. it could prove useful to other new Alas­ • arctic entries (double-door cold air • Sheetrock sealer and latex finish paint kans, I hope to make a cost study and traps) at the main entrances to the home; were used on all walls and ceilings to add comparison of building this type of home • multipane glazing in windows and to the vapor barrier effect. here and in Oregon. 2) I made provision in the house struc­ doors (triple panes in windows and dou­ • An oil-fired boiler was selected as the ture for setting solar collector panels on ble panes in doors); most economical option for heating via the roof and piping into the domestic hot • storm doors on the dining room and circulating hot water in baseboards, as water system. This application would be solar room doors; well as for providing hot water for domes­ mainly for summer use (April through tic uses. • 2-inch-thick polystyrene rigid insula­ October). tion as temporary exterior shutters over 3) I made provision for running hot most windows and the solar room sky­ ROOF water heating coils through the wood light during the coldest and darkest part Everyone who offered advice agreed stoves for winter use; this will be accom­ of winter; and on the use of a cold roof with free out­ plished as time and money permit. One • dark paint and shingles on the exterior side air circulation above 18 inches (R-60) must be very careful of where and how and a relatively large amount of glass in of blown-in insulation. This type of roof the heating coils are installed in order to the south-facing solar room to take advan­ minimizes such problems as ice damming prevent leak damage to house furnishings. tage of solar gain during the spring and 4) All problems mentioned in the ear­ fall months. lier sections will need monitoring and fol­ Some of the other features that were lowing up, especially those pertaining to included for energy-saving reasons as well permafrost and seasonal frost. as common-sense applications are: All things considered, I found the ex­ • A 4-foot roof overhang above the perience satisfying and, to all appearances, north walkway to the front arctic entry successful. Time will tell. +

24 The Northern Engineer, Vol.17, No.2 Remote Sensing in the North AN AUFEIS CASE STUDY by W. J. Stringer, T. H. George, and R. M. Bell DELTA LAND USE STUDY AREA

IN ALASKA, FLOODING OCCURS as a result of all the causes known to be responsible for floods in the temperate regions and, in addition, as a result of conditions unique to arctic and subarctic regions. SCALE APPROX. One of these conditions is the creation of aufeis, or 1•1,000,000 stream glaciering, that often blocks channels and 0 10 20 30 40 50 subsequently diverts stream waters during cold §©© months. This paper details the use of Landsat data kilometers to document one such flooding event and its impli· cations to land-use planning. During the spring of 1974 the Geophysicallnsti· tute and the Soil Conservation Service entered into a joint program to investigate the utility of Landsat data for identifying potential flood hazard areas in Alaska. The location chosen for this study was the Figure 1. The location and extent of the Big Delta land-use study area. Big Delta land-use planning area, an area approxi­ mately 120 by 40 miles centered at Delta Junction, Alaska, 100 The chief function of Landsat is to acquire photograph-like miles southeast of Fairbanks (Fig. 1 ). Landsat imagery and digital imagery of the earth which can be used for earth-resource or tapes were used to provide landform and vegetational information land-use analysis. The imagery is acquired by means of photo­ related to flood hazard analysis as well as historical flood data electronic sensors, each of which measures the light reflected by for the study area. the earth in a narrow wavelength band. Each sensor scans the earth in a systematic manner to generate an image. Lighter areas LANDSAT DATA on the image represent earth surface features reflecting large Detailed descriptions of Landsat data can be found in many quantities of energy in the wavelength being measured. The places. Here we will briefly describe only those aspects and wavelength bands measured by Landsat include green, red, and characteristics of the satellite data that have a direct bearing on two near-infrared wavelength bands. Although the term "infra­ this paper. red" is often associated with heat, the infrared region actually

W.J. Stringer, Associate Professor, Geophysical Institute, UAF, T. H. George, Applications Specialist, Geophysical Institute, UAF, and R.M. Bell, Water Resource Specialist (now retired), Alaska Soil Conservation Service, prepared the Information and Evaluation Report from which this article was taken: Identification of Flood Hazard Resulting from Aufeis Formation in an Interior Alaskan Stream. The research was funded principally by a grant from the Soil Conservation Service and in part by the National Aeronautics and Space Administration, Office ofUniversity Affairs. The Information and Evaluation Report was prepared for the Soil Conservation Service as part of a feasibility study to evaluate the utility of Landsat imagery for flood hazard analysis and conse­ quent land-use decisions.

The Northern Engineer, Vol.17, No.2 25 spans the electromagnetic spectrum all the way from red light to 100 miles) was such that at the equator the satellite captured microwave wavelengths. The two infrared bands monitored by images of adjacent locations on successive days, with an overlap Landsat lie just beyond the visible red wavelengths in the elec­ of about 10 percent. A given "scene" was repeated every 18 days. tromagnetic spectrum and are not in any way used as an indica­ At central Alaska latitudes, because the polar orbit paths con­ tion of heat. However, dry snow strongly reflects these two verge, the images therefore overlapped and images of a given wavelengths. Water, on the other hand, strongly absorbs radiation location were obtained 3 days in succession. At this time there in the infrared bands. are two Landsats in operation with their orbits arranged so that The most common data products available from Landsat are it is technically possible to collect images of a given location in the now-familiar black and white photograph-like images pro­ Alaska on 3 out of every 8 days. duced by the individual Landsat sensors. Each product is com­ monly referred to by the wavelength band that is monitored; AUFEIS thus, a "band 5 image" refers to the image produced by the sen­ sor monitoring red light reflected from the earth, while a "band Ice-forming situations occur all winter in arctic and subarctic 7 image" refers to an image representing reflected energy in the areas where there are continuous sources of water and freezing more red of the two infrared wavelength bands monitored. temperatures! An obvious example of this situation is that of a Each wavelength band monitored was chosen for its utility for stream fed by an active, year-round spring: the spring water will different aspects of resource and land-use analysis. Band 5, for be subjected to freezing temperatures and under most conditions instance, is especially useful for monitoring cultural features while will freeze somewhere along the stream. When new ice continues band 4 (green) is best for monitoring suspended sediments. to form on top of older ice, this condition is described by the The satellite travels around the earth approximately every 90 German term aufeis (literally, "upon ice"). Aufeis can build up minutes in a polar orbit. At the time this study was performed, to fill normal stream channels and cause the stream to flow onto the relationship between the orbit and the field of view (about the nearby flood plain where flooding waters freeze. During

An editorial interjection ... WHEN DOES INFORMATION BECOME KNOWLEDGE?

A year ago, Ken Dean contributed ':A-laskan Stream Icings" Fisher found authorities who could explain the cause for to this series on remote sensing in the north. His article dealt the soggy soil. "About 10,000 acres of what the state classi­ with tracking aufeis on a grand scale; the project on which fied and sold as small farms in land lotteries and auctions lie he reported was a search of the state for zones where the directly in the path of flooding from Jarvis Creek, according hazardous icings were likely to occur. The far earlier project to the Division of Agriculture.... Officials say the problem reported here, on the other hand, was small scale indeed. It may stem from a glaciating area along Jarvis Creek on Fort was a check of the satellite technology on one creek where Greely military lands." The State's agriculture director was aufeis was known to occur and where it created floods. As quoted: "I don't think anybody realized this happens every the article reports, the technology worked -and, as the Dean year." The appropriate Army Corps of Engineers section article indicated, is still working- quite well. That's nice, chief commented, "I don't think it glaciates in the same place but what does one do with a working technology and the every year." information acquired with it? In the case of this decade-old The contracts that the frustrated farmers signed guarantee study, no one employed the technology long enough, and that the State is not liable for natural or artificial hazards, the information it had gathered wasn't disseminated widely the appropriateness of the land classification, or whether the enough. land is profitable or fit to farm. The farmers, so to speak, Much of the area referred to in this article as "the Big were up the creek. Worse, Jarvis is not the only creek in the Delta land-use planning area" is now being developed for agri­ area to cause aufeis-related problems, and farms aren't the culture. Many thousands of acres in the vicinity have been only thing being threatened. Floodwaters from Jarvis Creek sold to individuals as a planned step in developing commer­ nibbled at the embankments of the Alaska Highway during cial agriculture in Alaska. The farmers there must deal with the spring of 1982 and again in 1983. high costs, short and erratic growing seasons, hungry (but Studies are under way, and the Soil Conservation Service legally protected) bison -and some also must deal with the was able to ease what could have been a truly disastrous situa­ overflow from Jarvis Creek. tion this past spring by cleaning and sanding the ice to speed The 1 June 1983 issue of the Fairbanks Daily News-Miner the melting of a channel. Yet even the studies aren't free, carried two front-page articles by Susan Fisher dealing with and whatever fix turns out to be feasible is certain to be glitches in the State's agricultural projects. One concerned expensive. delays with land transfers near Nenana; the other was head­ The story has two morals: first, aufeis is a true hazard, lined, "What happens when you can't farm the land?" It con­ one that is easier to avoid than ameliorate; second, informa­ centrated on the plight of two Delta families who bought tion and information-gathering technologies do make the land from the State of Alaska under the condition that they transition from theoretical to practical, from the premises develop farms upon it. The catch is that they can't: their of basic research to the potential for useful application -and land is too wet. when they get there, they ought to be applied.

26 The Northern Engineer, Vol. 17, No.2 normal spring runoff, waters flowing in such ice-filled stream chan­ nels can be diverted on­ to the adjacent flood plain.

DETECTING A FLOOD As part of the study of flooding potential, a search for historic flood data in the Big Delta area, all existing Land­ sat images available for map with rivers and aufeis­ that area were examined. related floodwater areas Images acquired 25 and outlined. The flooded areas were mapped from 26 April 1974 showed a the satellite-generated large dark area (particu­ photograph. Note that the larly on the infrared overflow from Jarvis Creek band images) several follows an old stream miles long lying to the east of Delta Junction. This condition was in­ terpreted as flooding be­ cause of the very strong absorption of bands 6 and 7 infrared radiation. Another part of the joint program of flood hazard analysis was a flood history report of the Delta area2 .based on existing records and in­ terviews of persons living in the area. A yearly flooding situation de­ scribed in this reportcor­ roborated what had been identified on the Land­ sat images: Jarvis Creek, also a tributary ofthe Del­ ta River, has created problems in the pop­ ulated Delta Junction area for a number of years. During breakup itjumps its channel as a result of ice block­ age, and several times has flowed in an al­ ternate route to the Delta River, running through a subdivision and past the airport. In the last ten years, however, a U.S. the stream sinks into porous ground, and is lost in a bog which Army-built block of this alternate channel has prevented stretches north to the Tanana River. Although this only hap­ flooding in the airport area. Since the Jarvis continues to pens once a year, the flow of water is great enough that two jump its banks yearly, it was forced to find another channel, large culverts are needed, and are frequently inadequate, to and now flows for approximately two weeks each spring along channel it under Jack Warren Road. 2 the west side of a (north-south) ridge which terminates just Wintertime flooding resulting from aufeis remains localized north of Jack Warren Road. Several hundred feet beyond this because low temperatures soon cause freezing of the flood waters

The Northern Engineer, Vol. 17, No.2 27 Figure 3. An oblique aerial photograph showing the lower (north) end of the Jarvis Creek aufeis formation, 1976. The water is being diverted from Jarvis Creek into an old channel at the upper left (arrow). (Note the drier creek bed in the center of the photo.)

near the stream diversion. In this particular case, during the peri­ river beds were brown, and ice (including aufeis) was red. This od in question, the daily temperatures ranged from near freezing combination of projected images was photographed and enlarged at night to 50"F during the day.3 Hence, the flood waters were to a 1-inch-to-the-mile scale. free to flow with little restriction. On the resulting photographic print, aufeis could be identified Although this springtime flooding had long been recognized on both Jarvis Creek and the Delta River as red while the snow­ in the Delta area, the source and extent of the flooding was not free bare river beds below these ice formations appeared brown. mapped prior to the analysis of the spring 1974 Landsat imagery. Several ice-covered lakes and ice pans on the Tanana River also Similar flooding was noted exactly a year later when at least one appeared to be red. Water and forests were various shades of local resident found it necessary to take action to divert similar green. flood waters. The distinction between these latter two features was clear everywhere except in one location. Here, topographic and vege­ DATA ENHANCEMENT TECHNIQUES tational data were used to distinguish between the flood waters and adjacent forest. Only those areas that could clearly be identi­ Although the flooded areas could be partially identified on fied as flooded were delineated. The problem of linking these Landsat band 7 images, the identification was somewhat ambigu­ areas with flowing flood waters remained. ous. In order to produce a more useful data product, a multispec­ A typical product of this process is shown in Figure 2, where tral approach was taken. After considerable experimentation, it the known flood and aufeis data from the photographic print of was found that the clearest distinction between the features of Landsat data have been transcribed onto a standard USGS inch­ interest could be obtained using imagery from two of the Land­ to-the-mile map. Because only one flooding event of unknown sat sensors. The technique combined data from these two relative magnitude was observed and since it is known that re­ sensors by simultaneously projecting data from the two wave­ peated floodings have taken place, statistical hydrologic consid­ length bands through colored filters onto a screen. (A commercial erations should be used to project the flood hazard onto adjacent optical device was used for this process, a "color-additive viewer" potentially flooded lands. manufactured by I2 S Corporation.) Band 5 (positive transparency) was projected as green, band 7 (positive transparency) as red, and FIELD RECONNAISSANCE band 7 (negative transparency) as white. The resulting colors of On 23 April 1976, approximately two years after the flooding surface objects had no relationship to their true colors; however, event mapped here, a reconnaissance of the Jarvis Creek area the flooded area could be distinguished as light green, while bare was made by light aircraft. That the repetitive nature of Jarvis

28 The Northern Engineer, Vol.17, No.2 Figure 4. Another oblique aerial photograph shows the bank-full ice condition of Jarvis Creek (foreground) in the region of the actual overflow, 1976. The water is flowing from the creek through the trees in the foreground and into an old stream bed or channel.

Creek flooding resulted from aufeis obstruction was borne out avoid placing structures and roads in areas likely to be afflicted by the discovery of the aufeis formation and resulting flooding with aufeis or aufeis-caused floods. Aufeis formation and related at the same location observed on the Landsat imagery. flooding should be major considerations in the design of any Figure 3 shows the lower (north) end of the aufeis formation construction project.4 For these reasons, the locations of aufeis on Jarvis Creek. The actual stream diversion (toward the left) formations should be accurately identified for land-use planning takes place at the location approximately in the center of the decisions in Alaska. The availability of several years' Landsat data photograph. Figure 4 shows the bank-full ice conditions at the should make possible flood hazard analysis for the many aufeis­ point of overflow. prone areas of Alaska where human activity is anticipated. At the time of this reconnaissance, the flooding could be fol­ lowed from the point of diversion to and beyond the Alaska REFERENCES Highway. Generally, the flood waters follow tree-lined ephemeral 1 stream channels between these two points, spreading out occa­ Carey, K. L. 1973. Icings Developed from Surface and Ground Water. Cold Regions Science and Engineering Monograph III-D3, U.S. Army sionally to fill low areas. Thus, it is possible for the flood waters Corps of Engineers, Cold Regions Research and Engineering Laboratory, to be confined within the narrow stream channels for portions of Hanover, NH. [This monograph is a good general review and reference their path, escaping detection by Landsat because the width of on the subject of stream icings.) these channels is too small to be detected by the sensors on the 2 Yarborough, L.F. 1974. Flood History of the Delta Junction Area. satellite. This explains why the flood could not be followed Report prepared for the Soil Conservation Service, Alaska State Office, continuously on the Landsat-derived image from the point of 204 E. 5th Ave., Anchorage, AK. [The report was prepared as part of the flood hazard analysis of the Delta study area and is based on avail­ diversion to the highway. able literature, interviews, and personal observations of the author.) 3 U.S. Army Atmospheric Science Laboratory. 1974. United States Army DISCUSSION Electronics Command Meteorological Team Data, Fort Greely, Alaska, Aufeis formation and consequent flooding are common to Central Meteorological Observatory, April. Atmospheric Science Lab­ arctic and subarctic climates and are a major source of springtime oratory, White Sands Missile Range, NM. [This publication lists hourly highway maintenance problems in these climatological areas. In meteorological data for the Delta Junction area.] 4 Alaska, floods resulting from aufeis formations often cause wash­ Sioan, C. D., C. Zenone, and L.R. Mayo. 1976. Icings along the Trans­ Alaska Pipeline Route. U.S. Geological Survey Professional Paper 979, outs on secondary roads during the spring; they can damage or 31 pp. [This paper documents icing conditions along the length of the destroy buildings and equipment. To date, despite extensive re­ pipeline route with maps and pictures. It also discusses some ofthe en­ search, the only truly effective remedy for aufeis problems is to gineering and land-use problems resulting from icing conditions.] +

The Northern Engineer, Vol. 17, No.2 29 • Noted nouncement of its program of home study • Meetings courses that help prepare people for the One of the unsung hazards of road, rail, registration exams-in this case, it's the Given our quarterly schedule-even and even air (at least on the runway end) April 1986 ones that they're aiming for. when we're on it-meeting announcements transportation in interior and southcentral Once again, we're letting you know that frequently arrive here a little too late for Alaska is moose in the right of way. It's a they exist, but please accept that that no­ us to give you timely notice. Such an­ year-round problem, but is worst in winter tice comes without commendation or cen­ nouncements then pass on to the great cir­ as deepening snow encourages the big ani­ sure. We've never heard from any of their cular file and are swiftly forgotten -that mals to follow cleared paths and darkness customers, satisfied or otherwise. is, they have been until this one. Sorry, makes it harder for drivers to spot them The ERS offering this year includes an even though you couldn't go until time in time to brake. engineer-in-training review course, two re­ travel is available in the north, here's the In Washington State, it's the smaller view courses in civil engineering, and one word on the 1985 Swedish Housing Exhi­ cousins of moose that cause the trouble; in electrical engineering. For more infor­ bition held this year near Stockholm: though a lighter-weight deer is less likely to mation, write Engineering Registration The exhibition motto was "Building for cause disasters to vehicles and their occu­ Studies, P.O. Box 24550, Los Angeles, Community." It incorporated product and pants in a collision than is a half-ton bull CA 90024, or phone them at (213) 208­ activity displays, conferences, seminars, and moose, vehicle-animal encounters there 5469. display homes, "examples of how different have killed people. They certainly kill Swedish developers [drawn, incidentally, many deer; according to the Washington from public, private, and cooperative ven­ State Department of Transportation, about tures) envision housing construction and John Zarling, professor of mechanical 500 deer a year have been killed in road management.... Housing areas will show engineering at the University of Alaska­ accidents there since 1981. both new production, rehabilitation and To cut the cervine carnage and protect Fairbanks and member of TNE's editorial infill in areas of multi-family housing and people and property, WSDOT tested a new board, has been voted chairman-elect of new forms for building single-family hous­ the Council of Sections for Zone 4 of the type of roadside reflector. The device takes ing." Work under way was to be part of the American Society for Engineering Educa­ advantage of the susceptibility of deer to exhibition, demonstrating the activities of being virtually hypnotized by bright light. tion. not only carpenters and landscape archi­ These "Swareflex" reflectors cast back the tects but also artists and furniture manu­ light from car headlights at right angles to facturers. It all sounded thorough and the roadway, creating an optical fence that impressive, but what was most impressive causes deer to remain motionless off the Note to Subscribers was the scope of the exhibition: "Three road until the car has passed. The reflec­ housing areas containing over 500 homes We've found another way in tors were installed on portions of a 2.3­ which Alaska is like a rather under­ are being built for the Exhibition...."Five mile section of a road in northeastern developed country. Sometimes our hundred! Clearly, Sweden is giving a fair Washington that l"lad had a high deer-kill Canadian readers pay for their sub­ priority to modernizing its housing. rate. The WSDOT covered and uncovered scriptions in their own dollars, work­ the reflectors at regular intervals between ing in (honest devils that they are) late fall and early spring from February the appropriate fudge factors for 1981 to March 1984. The effects were In the first article in this issue, author whose dollar is where on the shifting dramatic. In one portion, no deer were Rich Seifert discusses the accomplish­ international currency market. It's killed when the reflectors were in use vs. ments of some Scandinavian innovators. never been much of a problem be­ 11 dead when the reflectors were covered; Two of the significant members of that fore, but now-presumably in keep­ in the portion most heavily travelled by cadre will be in North America early in ing with Alaska's determination to the animals, 6 were killed while the reflec­ 1986: both Ann Thulin, architect for the encourage tourism and international tors were uncovered, but 52 died during Landskrona project discussed on p. 6, and trade-it's become extremely expen­ the intervals when the reflectors were Peter Broberg, founder of the Landskrona sive. The bank with the University's covered. Group, will be participants in Winter Cities account charges $7.50 (U.S.) per The report on this study can be ob­ Forum '86, to be held 15-19 February in check to translate Canadian into U.S. tained from the Washington State Depart­ Edmonton, Alberta. dollars. (It is the National Bank of ment of Transportation Research Office, For that matter, so will many other im­ Alaska, so they may not be too sure Transportation Building, KF-01, Olympia, pressive names (and titles-from the Mayor about the reality of money beyond WA 98504. of Sapporo to the members of the United the borders.) So please, when you Nations Economic Commission for Europe pay, make it in $U.S. We can't afford Committee on Housing, Building, and Once again, the firm known as Engineer­ it any other way. Planning). These people represent diverse ing Registration Studies has sent us an an­ areas of expertise; architects and engineers

30 The Northern Engineer, Vol. 17, No. 2 • Noted nouncement of its program of home study • Meetings courses that help prepare people for the One of the unsung hazards of road, rail, registration exams-in this case, it's the Given our quarterly schedule-even and even air (at least on the runway end) April 1986 ones that they're aiming for. when we're on it-meeting announcements transportation in interior and southcentral Once again, we're letting you know that frequently arrive here a little too late for Alaska is moose in the right of way. It's a they exist, but please accept that that no­ us to give you timely notice. Such an­ year-round problem, but is worst in winter tice comes without commendation or cen­ nouncements then pass on to the great cir­ as deepening snow encourages the big ani­ sure. We've never heard from any of their cular file and are swiftly forgotten -that mals to follow cleared paths and darkness customers, satisfied or otherwise. is, they have been until this one. Sorry, makes it harder for drivers to spot them The ERS offering this year includes an even though you couldn't go until time in time to brake. engineer-in-training review course, two re­ travel is available in the north, here's the In Washington State, it's the smaller view courses in civil engineering, and one word on the 1985 Swedish Housing Exhi­ cousins of moose that cause the trouble; in electrical engineering. For more infor­ bition held this year near Stockholm: though a lighter-weight deer is less likely to mation, write Engineering Registration The exhibition motto was "Building for cause disasters to vehicles and their occu­ Studies, P.O. Box 24550, Los Angeles, Community." It incorporated product and pants in a collision than is a half-ton bull CA 90024, or phone them at (213) 208­ activity displays, conferences, seminars, and moose, vehicle-animal encounters there 5469. display homes, "examples of how different have killed people. They certainly kill Swedish developers [drawn, incidentally, many deer; according to the Washington from public, private, and cooperative ven­ State Department of Transportation, about tures) envision housing construction and John Zarling, professor of mechanical 500 deer a year have been killed in road management.... Housing areas will show engineering at the University of Alaska­ accidents there since 1981. both new production, rehabilitation and To cut the cervine carnage and protect Fairbanks and member of TNE's editorial infill in areas of multi-family housing and people and property, WSDOT tested a new board, has been voted chairman-elect of new forms for building single-family hous­ the Council of Sections for Zone 4 of the type of roadside reflector. The device takes ing." Work under way was to be part of the American Society for Engineering Educa­ advantage of the susceptibility of deer to exhibition, demonstrating the activities of being virtually hypnotized by bright light. tion. not only carpenters and landscape archi­ These "Swareflex" reflectors cast back the tects but also artists and furniture manu­ light from car headlights at right angles to facturers. It all sounded thorough and the roadway, creating an optical fence that impressive, but what was most impressive causes deer to remain motionless off the Note to Subscribers was the scope of the exhibition: "Three road until the car has passed. The reflec­ housing areas containing over 500 homes We've found another way in tors were installed on portions of a 2.3­ which Alaska is like a rather under­ are being built for the Exhibition...."Five mile section of a road in northeastern developed country. Sometimes our hundred! Clearly, Sweden is giving a fair Washington that l"lad had a high deer-kill Canadian readers pay for their sub­ priority to modernizing its housing. rate. The WSDOT covered and uncovered scriptions in their own dollars, work­ the reflectors at regular intervals between ing in (honest devils that they are) late fall and early spring from February the appropriate fudge factors for 1981 to March 1984. The effects were In the first article in this issue, author whose dollar is where on the shifting dramatic. In one portion, no deer were Rich Seifert discusses the accomplish­ international currency market. It's killed when the reflectors were in use vs. ments of some Scandinavian innovators. never been much of a problem be­ 11 dead when the reflectors were covered; Two of the significant members of that fore, but now-presumably in keep­ in the portion most heavily travelled by cadre will be in North America early in ing with Alaska's determination to the animals, 6 were killed while the reflec­ 1986: both Ann Thulin, architect for the encourage tourism and international tors were uncovered, but 52 died during Landskrona project discussed on p. 6, and trade-it's become extremely expen­ the intervals when the reflectors were Peter Broberg, founder of the Landskrona sive. The bank with the University's covered. Group, will be participants in Winter Cities account charges $7.50 (U.S.) per The report on this study can be ob­ Forum '86, to be held 15-19 February in check to translate Canadian into U.S. tained from the Washington State Depart­ Edmonton, Alberta. dollars. (It is the National Bank of ment of Transportation Research Office, For that matter, so will many other im­ Alaska, so they may not be too sure Transportation Building, KF-01, Olympia, pressive names (and titles-from the Mayor about the reality of money beyond WA 98504. of Sapporo to the members of the United the borders.) So please, when you Nations Economic Commission for Europe pay, make it in $U.S. We can't afford Committee on Housing, Building, and Once again, the firm known as Engineer­ it any other way. Planning). These people represent diverse ing Registration Studies has sent us an an­ areas of expertise; architects and engineers

30 The Northern Engineer, Vol. 17, No. 2 will be playing leading roles, but clothing designers and other professionals will be involved also. A museum exhibition ac­ companying the Forum will show "100 years of dressing for the cold" and offer A d.a r~'n... opportunities to have clothing photo-tested for heat loss and to query a computer pro­ gram on how to dress more effectively to .. -an 1lP- ;;­ I ~ : i ' T~~ I~ I ! I ward off the cold. Since the theme of the : . : ' ' . : I I ' ' ! I . • ~ I ' i ' . meeting is "Towards the Livable Winter : I i j-,'\./...,'}.1..' i ~~~-" ' ' I I " : I i .. City," people come in for a fair share of : . : r:--~~· ~;:; ~ . ;.,. I .....:.~ ....-~."~ , . I ..... ~.. attention - including their recreational *"' ... : "' ·r·"L." ~ ,.-,_.., ... ! I .• • 1\Jj 1.•'· I I I I \h\\!1":"" ... preferences. One group of presentations I ~ ;; I I ·• :: r·: i I I r·•y. ·• will consider winter carnivals (Edmonton F;h~rn ~S1 p, ''t : I llolr. l -~ itself is offering a weekend of festivities, - ,::: I .,. from ice sculpture to indoor theatre, dur­ ~ ·"-~ ~' ~- - - '~ - - ~· ·" - .,. "'"' --· ~- '"'-'' ing the meeting). and one postconference f d: /. excursion is to an Oilers hockey game. v A core concern of the Forum on the Errata: As the accompanying cartoon indicates, our last issue wasn't perfect. technical side will be enclosures, from the First, and most grievous. we fell under the control of some mindless gremlin when Swedish "greenhouse streets" to Edmon­ it came time to paste in the labels for the temperature charts on pp. 18 and 19 in ton's own Hub Mall, a mixed-use neighbor­ Sue Ann Bowling's article, "Water, Ice, Land, and the Alaska Climate." The labels hood under glass. One featured speaker were transposed: Shemya is represented on page 18, St. Paul on 19-just there- will discuss the business end of building verse of the way we printed it. In that article also, we moved Shemya; the map on an enclosed town within a town in north­ page 17 shows its location, but the lying text directly above the map claims it is ern Ontario, so the financial aspects are only "two-thirds of the way along the Aleutians." Bah! to be covered as well. Dr. Bowling, incidentally, was most understanding about our human frailty. Fee for the Forum is $295 Canadian; None of us limped for longer than three days, and she will soon provide another special student rates are available, as are article related to Alaska's climate and weather. discounts to any municipality or company One of the gremlin clan struck again on page 22. We believe it was at the printer's registering five attendees. Forms or fur­ that Barter Island became "arter land" at the edge of that photo, but there's no ther information are available from Ami way to be certain that we didn't do it here. Fullerton or Pamela Freeman, Winter Cities Since that flaw fell in Kristina Ahlnas' article, it might seem that the gremlins Conference Corporation, 3rd floor City were sexist, bent on discrediting our women authors. However, on page 27, Hall, Edmonton T5J 2Rl, Canada; phone Robert Crosby was assigned a nonexistent address; his Biorealis Systems firm is (403) 428-3576. actually located at 508 W. 2nd in Anchorage, not W. E St. as we had it. If there were more errors, please don't tell us. There's only so much we can stand. What, you may well ask, will the XII Congress of the International Union for Quaternary Research have of interest for attending. For further information, write case studies, discussing instrumentation, engineers? Lots, as it turns out. Other than K. Charbonneau, Conference Coordinator, and considering the problems related to the generally interesting topics covered in National Research Council of Canada, Ot­ sparse data bases.) the more basic sessions (Quaternary extinc­ tawa, Ontario K1A OR6, Canada. For further information, write to the tions, archaeology). the applied sections symposium program chairman: Dr. Douglas should provide directly useful informa­ L. Kane, Institute of Water Resources/En­ tion. Under Quaternary Resources, for ex­ gineering Experiment Station, University ample, will be sessions on remote sensing, Coming on 22-25 July 1986: the annual ofAlaska-Fairbanks, Fairbanks,AK99775­ on protection of the natural environment, Cold Regions Hydrology Symposium. The 1760. on engineering problems in terrestrial American Water Resources Association is Quaternary deposits, and one on those the symposium sponsor, in cooperation problems in offshore deposits as well. Field with the University of Alaska; the AWRA The 10th Triennial Congress of the In­ trips to be held in association with the considers this gathering an International ternational Council for Building Research, Congress offer diverse views of Quaternary Specialty Symposium. The preliminary Studies, and Documentation (CIB) will be aspects of Canada, ranging from a 12-day announcement received here indicates that held 21-26 September 1986 in Washington, raft trip on the Coppermine River to a 4­ the presented papers will be grouped in DC. The organizing committee expects ap­ day tour of glacial and glaciomarine stra­ three general categories: hydrologic proc­ proximately 1000 people to attend, and tigraphy between Ottawa and Montreal. esses in cold regions, management of water about 150 papers will be presented. The Although the Congress will not be held resources in cold regions, and special top­ theme of this Congress is "Advancing Build­ until 1987 (31 July to 9 August). at the ics related to cold regions hydrology. ing Technology," and one of the meeting's Congress Centre in Ottawa, the organizers (That last section, incidentally, isn't a catch­ explicit aims is "to explore the latest in need to know soon if you are interested in all. It will provide a forum for presenting building technologies," according to the

The Northern Engineer, Vol. 17, No. 2 31 announcement received here. The Con­ word "environmental" has become a warn­ intended to spray adjacent forest lands gress is also aimed at helping people in the ing flag in some quarters, a signal that we with dangerous herbicides concludes on a field forge links across national and disci­ are entering an ideal world in which minds protest about "the use of a one-sided film plinary boundaries, as the announcement are disengaged and all the electricity we'll to attack biases in law and politics." It's notes opportunities "to develop associa­ ever need will be generated by hope spring­ an opinionated publication but makes a tions with international and U.S. organiza­ ing eternal-if only They will stop doing fair effort to keep facts to the front; even tions" and colleagues, and to accommo­ Bad Things and harken to the wonderful when the point of view is exasperating, date the "best integrated knowledge from ways of Nature. That's not the case with the argument makes good reading. Sub­ physical sciences, engineering, architec­ Alternatives. scriptions to Alternatives are $15 (Canadi­ ture, planning, economics, and behaviorial Certainly the staff's editorial philoso­ an) per volume (four issues) for individuals sciences." The Congress is being organized phy is very clear, and it is, so to speak, and $20 for institutions; the address is by Noel J. Raufaste, Director CIB 86, very green: they're in favor of living so as c/o Faculty of Environmental Studies, Center for Building Technology, National to keep the planet habitable (and beauti­ University of Waterloo, Ontario N2L 3G 1, Bureau of Standards, Gaithersburg, MD ful) for longer. Yet they don't present tech­ Canada. 20899. nology as the villain but as a set of tools, and-metaphorically-they decry the use of a sledgehammer when tinsnips would More focussed and less philosophical is do a better job. This magazine also does Bio-Joule, which concentrates on biomass • Publications some exuberant and eloquent decrying; it's as a source of energy-in fact, it is a publi­ well written and graphically attractive. cation of the Biomass Energy Institute. Like a little kid joggling a mechanic's While it goes on uncovering erroneous Its News section ranges quite widely, how­ elbow-Whatcha doin', mister?-we are and inappropriate applications, Alterna­ ever; noted in the July 1985 issue, for always pestering our neighbors to the east tives also conveys a great deal about what example, was a report on a joint U.S.­ for news of their endeavors and opinions in is going on in Canada, from where the Canadian conference on acid rain, one on the realm of technological development next dam may be built to how Canadian shipboard incineration of hazardous waste, in the north. Although a Canadian cousin law deals with the pursuit of international and the publication of a book on hydro­ to The Northern Engineer hasn't shown polluters. Though its writers can deal sav­ power development, among others. Simi­ up yet, we have encountered some publica­ agely with identified villains (an article on larly, although the magazine emphasizes tions that overlap a few of our concerns. mismanagement of northern Ontario's bor­ relevant Canadian work in its articles, it Alternatives, which describes itself as an eal forests, appearing in the fall1984 issue, is not limited to reporting on one nation's "environmental quarterly," has been pub­ surely must have led to governmental in­ endeavors. That July issue included a re­ lished since 1971; the magazine recently vestigations, lawsuits, or both). being on port on the city of Los Angeles Hyperion moved its base of operations from Trent the "right" side is no guarantee of gentle Energy Recovery System project, which University in Peterborough to the Faculty treatment: the review of a film document­ will generate nearly 25 MW of electricity of Environmental Studies at the University ing the case of 15 Cape Breton landowners as a byproduct of sewage treatment. The of Waterloo, both in Ontario. Now, that against a multinational corporation that periodical is brisk in tone, with many brief

• Book Reviews Dr. McBeath and her conference co-organizers also understood that if the far north becomes warmer, it will not be only new sea levels and different harvest times for which the residents need to The Potential Effects prepare. Northern engineers might prepare specifically for some of Carbon Dioxide-Induced Climatic Changes in Alaska significant but logically predictable changes in their environment. The Proceedings of a Conference The Arctic Ocean may be virtually ice free in summer, but will Jenifer H. McBeath, Editor still be ice covered in winter. Continuous-zone permafrost will Glenn P. Juday and Gunter Weller, Assoc. Editors persist but be covered with a thicker active layer, while the more Mayo Murray, Technical Editor southerly discontinuous permafrost will diminish, or even van­ Miscellaneous Publ. 83-1 of the School of Agriculture and Land Resources ish. There will be thaw consolidation and thermal erosion in both Management; 208 pp.; available free on request from Ms. Murray at zones, with all the challenges those imply for human activity. Room 309 O'Neill Resources Building, Agricultural Experiment Station, Thus, for example, the integrity of the trans-Alaska pipeline University of Alaska-Fairbanks, Fairbanks, AK 99775-0080. could be threatened by collapsing thawed soil, while tankers The carbon-dioxide measurements from Mauna Loa and Ant­ may be able to traverse the Arctic Ocean. arctica yield graphs that look like ascending staircases: the earth's Other likely consequences are more surprising. Most of Alaska atmosphere contains more C02 every year. This volume contains should receive more precipitation than it now does, although the 24 papers discussing many aspects of what that extra carbon Interior might well be drier-discounting the suggestion of one dioxide will mean to Alaska. author that rising sea levels could create "a salt water bay in the The C02 increase is a hot topic in both senses of the phrase. Yukon Valley bounded by the peninsulas of the Brooks and One of its effects is likely to be higher temperatures, especially Alaska ranges." Rather than simply melting away, glaciers first near the poles. But what exactly that warming will produce here may advance; so may taiga forests and boggy swamps. is disputable, and disputed. As one of these authors admits, "our The book has been carefully edited for clarity and readability; tools for predicting what regional changes will take place are diverging views have not been disguised, and data gaps have not rather dull, and the crystal ball that we have to look at is very been bridged with imaginative speculation that is not so labelled. foggy...." Almost every northerner should find facts and opinions that are

32 The Northern Engineer, Vol. 17, No.2 reports (the longest article in the issue re­ and practical guide to environmentally example, John J. Burns, one of the world's viewed here was four pages). The editorial hazardous products. This manual provides experts on pinnipeds, wrote a chapter on assumption appears to be that the readers essential information about chemical sub­ living resources). The time frame empha­ are reasonably comfortable with a fair stances considered hazardous upon spillage sizes the present and near future; the range of technology, for there are no digres­ including instructions on control, contain­ book's subtitle is "The 1980s and 1990s." sions to define "substoichiometric zone" ment, disposal and treatment for contam­ The 384-page book costs $35 and is or "sequencing and homology studies." ination," according to the advertisement available from Springer- Verlag Inc., P. 0. Subscriptions are $20 (Canadian) per received here. The volume also contains Box 2485, Secaucus, NJ 07094. year (six issues). The magazine may be or­ quantitative data on chemical and physical dered from The Biomass Energy Institute, properties, fire properties, human health 1329 Niakwa Road, Winnipeg, Manitoba and toxicity, reactivity and environmental Elsewhere in the Back of Book, we note R2J 3T4, Canada. toxicity. It costs $18.95 within Canada, the forthcoming Cold Regions Hydrology $22.75 elsewhere- or the equivalent in Symposium; we hereby note the existence non-Canadian currency. It may be ordered of the Proceedings from earlier meetings Similar to Bio-Joule in interests but very from booksellers or directly from the Cen­ in this annual series. Since the symposia different in form is the Alaska Bioenergy tre in Ottawa, Ontario K1A OS9, Canada. have not had specific themes, each of the Quarterly Report. This newsletter notes volumes covers a great diversity of topics the existence of relevant publications and within the field. This field is broad and pertinent projects, chiefly in Alaska but United States Arctic Interests "outlines not yet extensively researched; thus, few also in the contiguous United States. Edi­ the full range of U.S. Arctic interests, and of the papers will be outdated soon. In­ tor Wendi Sollenberger presents the head­ articulates the manner in which these mul­ formation is available from AI Paulson, lines and lets readers write or call for more tiple, sometimes conflicting, interests are Editor, Institute of Water Resources/En­ details on any item they find worth follow­ related to one another." So says the pub­ gineering Experiment Station, University ing up. A subscription to the newsletter is lisher's announcement of this book, and ofAlaska-Fairbanks, Fairbanks, AK99775­ available free on request to her at the Alas­ the list of authors and chapter titles makes 1760. The cost will vary depending on ka Bioenergy Program, Office of Energy, the claim seem reasonable. Editors William length, but these are all reasonably priced 3601 C St., Suite 722, Anchorage, AK E. Westermeyer and Kurt M. Shusterich, books. 99503. both of Woods Hole Oceanographic Insti­ tution, have attempted to provide a broad perspective on matters from the political Now available from the Swedish Council The Canadian Government Publication (Elliot Richardson provided the foreword, for Building Research are the Proceedings Centre is purveying the Manual for Spills which presumably would be written from volumes for an international conference of Hazardous Materials. Prepared by the his international and national experience; on Subsurface Heat Storage in Theory and Technical Services Branch of Environment Eugene Brower, a name well known in the Practice. The conference itself was held in Canada and available in English or French, politics of the North Slope Borough, is co­ Stockholm in 1983; a two-year preparation the book is billed as "a comprehensive author of a chapter) to the biological (for (Continued on p. 35)

interesting and thought-provoking in this Proceedings, but only that same year, Castner succeeded in spite of Army "impedi­ time will tell if any of its contents prove pragmatically useful. mentia" (his word), poor sketch maps and guidance, loss oftools -Editor and supplies, and near starvation. His exploratory trek took the entire summer of 1898, and he returned to southeast Alaska by Lieutenant Castner's Alaskan Exploration, 1898 dogsled in the deadly cold of the following winter. A Journey of Hardship and Suffering The editor of Castner's account of his term in Alaska, historian Edited by Lyman L. Woodman Lyman Woodman who is himself a retired military officer, based 90 pp.; published by and available from the Cook Inlet Historical Society, the book on a speech Castner gave in 1909 and used some excerpts 121 W. Seventh Ave., Anchorage, AK 99501; $8 plus $1 for postage and from his government reports to add setting and details to the handling. story. He lets Castner speak for himself, and the young lieutenant Lieutenant Joseph C. Castner was 29 years old when he broke speaks well-even with his turn-of-the-century naivete. His tale trail from Cook Inlet to the Yukon River. The young Army offi­ of exploration is full of information and honest and insightful cer, who was just beginning a distinguished military career, was observations. serving his Alaska stint at that time under Captain E. F. Glenn. The book itself, after a confusing beginning with prefatory The party's general orders included discovering "the most direct material not clearly separated from Castner's account, is nicely and practicable route from tidewater to one or more crossings done. The use of symbols to "source" every paragraph does not of the Tanana River in the direction of the Yukon." interfere with the story and makes the document easy to use for This assignment went to Castner, who forged a trail ahead of historic research. The few photographs, primarily pictures taken the Glenn company. His tools were meager provisions, orders, by USGS geologists, illustrate the text so well that the reader and men; ailing Army mules; and one faithful horse. His party wants more-especially those mentioned in the narrative that crossed glaciers, mountains, and swollen streams; they mucked were taken by camera-carrying geologist W. C. Mendenhall who through swamps, hacked through forests, tried to escape mosqui­ accompanied the Glenn party. tos, and dealt with Alaska's Native inhabitants who sometimes Woodman's editing has combined Castner's clear, logical re­ seemed threatening but who ultimately saved their lives. Deter­ porting with his story-telling abilities to present an easy-to-read mined to reach Circle City and to return to report his findings Alaskan adventure with historic pertinence. -KFM, Assoc. Ed.

The Northern Engineer, Vol. 17, No.2 33 temperature at the north end and the south end also are some­ • Letters what less. Have currents, must travel Where these two currents meet is along that chain of islands Editor: called the Aleutians which is in reality a chain of partially sub­ Having read the recent article entitled "Water, Ice, Land, and mersed mountains. The mixing and interchange of temperatures the Alaska Climate," I think some comments are warranted. is irregular, sporadic, and cyclic according to the time of year. First, the article states that "Shemya is about two-thirds of There may be records to show the speed, volume, and temp­ the way along the Aleutians." Having spent time there as an en­ erature of these currents but we have never had an opportunity gineer during World War II, I am reasonably sure the location is to study these. It seems as though the time of year when the much further out toward the end of the chain. It is in sight of warmest part of the Pacific current reaches Shemya might have Attu, which is the furthermost point. I believe I recall the dis­ a large effect on how severe our winters are and how much tance between the two islands as being about 35 miles. moisture is passed into the air, resulting in varying amounts of Also, it appears the charts for St. Paul Island and the one for snowfall and rain. More study on this should be very valuable Shemya are mixed up. [Right! See errata, p. 31.-Editor.] for longer term weather prediction. I don't see any discussion of the ocean currents and their The evaporative effect of the ocean water on the air tempera­ strong effect on the local temperatures and the climate. The ba­ ture above is tremendous, and when the seas are rough with high sic current in the Pacific area south of the Aleutian Chain is a wind conditions this is greatly increased. Examine the humidity clockwise one which flows west at the Equator, then north of those air masses flowing across the Siberian land toward along the coast of the Philippines, Japan, China, Korea, etc., Alaska and visualize how the vapor pressure will influence a high then east just south of the Aleutians until it reaches the Gulf of rate of evaporation with nearly 1000 BTU of cooling effect for Alaska where it turns south flowing down to Canada, Washing­ every pound evaporated. This evaporation rate drops dramatically ton, Oregon, California, and Mexico to the Equator where it re­ as the Pacific current flows south and as the air above it is influ­ turns westward again. enced by the great mass of the Pacific across which the air cur­ The basic current pattern in the Bering Sea also flows clock­ rents have flowed. wise, going west along the northern side of the Aleutians to Si­ As to the effect of the mountains, large land masses, etc., beria, then north to the vicinity of St. Lawrence Island where it there is a completely different and much more complex set of turns east, flowing to the coast of Alaska near Nome and then factors (and to me this is a completely different subject). For returning south to the Aleutians. our heating calculations we allow about 5 to 10 degrees above Where these two currents meet along the Aleutian Chain is the lowest recorded temperatures at or very close to the coast. created a great mixture of waters with a wide contrast of temp­ Then we increase this as the distance from the ocean or sea in­ erature. This in turn causes this area to be labelled the "birth­ creases until at about 100 or 150 miles inland we use a design place" of our storms for the North American continent. temperature of 20 to 25 degrees above the lowest recorded. The waters of the Pacific, as they start north along the Phil­ This is influenced to some degree by the hours of daylight and ippines up past Guam, warm to about 85 or 90 degrees depending the general climate history, of course. on the time of year, the depth of the water, the proximity to Ice-covered water has much less effect on air masses than liq­ shore, etc. As this current flows northward it cools down grad­ uid water for many reasons such as the dead air layer close to ually, reaching temperatures of about 40 to 50 degrees as it turns the surface, no disturbance of the surface or change of area such east. Then it continues to cool down until it reaches the Gulf of as occur with waves, a much lower vapor pressure, etc. Alaska where its temperature approaches 35 degrees. From here Anyhow, the article was very interesting and I would think it flows south, warming very gradually until it reaches Baja Cali­ you are starting on the path to developing a more reliable method fornia where it is back up to 65 or 70 degrees again. This has a of understanding some of the causes of our erratic climate phe­ major effect on the temperature and climate of the adjacent nomena. We need a much better history of the movement of the land masses and has a strong influence for 50 to 150 miles in­ air masses through the summer and winter seasons which should land depending on the terrain. be developed from accumulation of airport data and pilot obser­ In turn, the waters of the Bering Sea go through much the vations. If this should be properly gathered and evaluated, much same cycle; since the area is so much smaller and the volume is of the mystery of our climate would be dispelled. less, its influence is reduced and the time the current takes to Dan Vandament, P. E. make its full travel here is very much less. The difference in its Anchorage, Alaska

Dr. Bowling responds: Dear Mr. Vandament, lowance for the length of the record and the microclimate of Shemya is indeed at the end of the Aleutians (the two-thirds exactly where it was recorded? Here in Fairbanks, you could take referred to Adak, which was the oceanic station I started to use). the record for the last 10 years and get a record low of -52oF. and St. Paul and Shemya were reversed during the printing proc­ The current site record is actually - 62oF, and - 66°F was re­ ess. My apologies, especially on the location of Shemya. corded when the Weather Bureau was located downtown. The The ocean currents in the North Pacific are indeed very impor­ situation may have corrected itself by the time this is printed, tant to the meteorology of the region, and an interesting article but we've had a run of warm winters all over Alaska, and records could be written about them. However, that was not the article less than about twenty years in length may be very misleading I was writing. Perhaps TNE could twist some oceanographer's about actual minimum temperatures. arm for an article? S. A. Bowling One thing I do wonder about in your letter: when you use the Fairbanks, Alaska lowest recorded temperature in your planning, do you make al-

34 The Northern Engineer, Vol. 17, No.2 Systems and Accessibility Potentials in • Publications The set costs 262 kronor, including air (Continued from p. 33) mail postage (the U.S. dollar was equiva­ Europe," "Britain and Sweden: Premature Obsolescence of Housing," and "Research time is not unusual for a summary pro­ lent to about 9 Swedish kronor at press on areas with single-family houses on es­ ceedings, and given that this one fills 1000 time). It may be ordered from the Council pecially small lots." Although this publi­ pages, the prepublication duration is rea­ atBox 7853,S-103 99Stockholm,Sweden. cation is sold by the Swedish firm of sonable. The three volumes thoroughly Almqvist & Wiksell Periodical Company document the entire conference, including (P.O. Box 45150, S-104 30 Stockholm). presentations on heat storage and extrac­ Scandinavian Housing and Planning Re­ the membership of its advisory and editor­ tion in rock caverns and pits, in soil, in search is a quarterly journal devoted to the ial boards and the number of its sponsor­ lakes, and in aquifers. Twenty papers cover social science aspects of the field; it's an ing agencies indicate that it will cover all simulation models in theory and practice, interdisciplinary approach toward policy Scandinavia from Iceland to Finland. An­ and four discuss the role of energy storage problems at local to international levels. nual subscriptions are 350 Swedish kronor in national energy systems; there are 130 Articles published in 1985 included titles for institutions, 190 for individuals. papers in all. such as "Metropolitan Transportation +

35 The Northern Engineer, Vol. 17, No.2 THE NORTHERN Nonprofit Organization ENGINEER U.S. Postage PAID @)GEOPHYSICAL INSTITUTE Permit No.2 UNIVERSITY OF ALASKA·F AIRBANKS FAIRBANKS, ALASKA 99775·0800 Fairbanks, Alaska 99775 -Address Correction Requested-